Convert.ToUInt16 方法

參考

定義

命名空間:: System

組件:: System.Runtime.Extensions.dll

組件:: System.Runtime.dll

組件:: mscorlib.dll

組件:: netstandard.dll

重要

部分資訊涉及發行前產品，在發行之前可能會有大幅修改。 Microsoft 對此處提供的資訊，不做任何明確或隱含的瑕疵擔保。

將指定的值轉換為 16 位元不帶正負號的整數。

多載

ToUInt16(String)	將指定之數字的字串表示，轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(UInt16)	傳回指定的 16 位元不帶正負號整數；不會執行實際的轉換。
ToUInt16(UInt32)	將指定的 32 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。
ToUInt16(String, Int32)	將指定基底中數字的字串表示，轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Object, IFormatProvider)	使用指定之特定文化特性格式資訊，將指定之物件的值轉換為 16 位元不帶正負號的整數。
ToUInt16(String, IFormatProvider)	使用指定之特定文化特性格式資訊，將指定之數字的字串表示轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Single)	將指定之單精確度浮點數的值，轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(UInt64)	將指定的 64 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。
ToUInt16(SByte)	將指定的 8 位元帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。
ToUInt16(Char)	將指定的 Unicode 字元值轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Int64)	將指定的 64 位元帶正負號的整數值轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Int32)	將指定的 32 位元帶正負號的整數值轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Int16)	將指定的 16 位元帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。
ToUInt16(Decimal)	將指定之十進位數字的值，轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(DateTime)	呼叫這個方法一律會擲回 InvalidCastException。
ToUInt16(Byte)	將指定的 8 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Boolean)	將指定的布林值轉換為相等的 16 位元不帶正負號的整數。
ToUInt16(Object)	將指定之物件的值轉換為 16 位元不帶正負號的整數。
ToUInt16(Double)	將指定之雙精確度浮點數的值，轉換為相等的 16 位元不帶正負號的整數。

ToUInt16(String)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定之數字的字串表示，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::String ^ value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string? value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : string -> uint16

Public Shared Function ToUInt16 (value As String) As UShort

參數

value: String

字串，包含要轉換的數字。

傳回

UInt16

與 value 中之數字相等的 16 位元不帶正負號的整數；如果 value 為 null，則為 0 (零)。

屬性: CLSCompliantAttribute

例外狀況

FormatException

value 不是由後面接著一連串數字 (0 到 9) 的任意符號所組成。

OverflowException

value 代表小於 UInt16.MinValue 或大於 UInt16.MaxValue 的數位。

範例

下列範例會嘗試將數值字串陣列中的每個項目轉換成16位無符號整數。

string[] values = { "1603", "1,603", "one", "1.6e03", "1.2e-02",
                    "-1326", "1074122" };
ushort result;

foreach (string value in values)
{
   try {
      result = Convert.ToUInt16(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (FormatException) {
      Console.WriteLine("The {0} value {1} is not in a recognizable format.",
                        value.GetType().Name, value);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the UInt16 type.", value);
   }
}
// The example displays the following output:
//    Converted the String value '1603' to the UInt16 value 1603.
//    The String value 1,603 is not in a recognizable format.
//    The String value one is not in a recognizable format.
//    The String value 1.6e03 is not in a recognizable format.
//    The String value 1.2e-02 is not in a recognizable format.
//    -1326 is outside the range of the UInt16 type.
//    1074122 is outside the range of the UInt16 type.

let values =
    [| "1603"; "1,603"; "one"; "1.6e03"
       "1.2e-02"; "-1326"; "1074122" |]

for value in values do
    try
        let result = Convert.ToUInt16 value
        printfn $"Converted the {value.GetType().Name} value '{value}' to the {result.GetType().Name} value {result}."
    with
    | :? FormatException ->
        printfn $"The {value.GetType().Name} value {value} is not in a recognizable format."
    | :? OverflowException ->
        printfn $"{value} is outside the range of the UInt16 type." 
// The example displays the following output:
//    Converted the String value '1603' to the UInt16 value 1603.
//    The String value 1,603 is not in a recognizable format.
//    The String value one is not in a recognizable format.
//    The String value 1.6e03 is not in a recognizable format.
//    The String value 1.2e-02 is not in a recognizable format.
//    -1326 is outside the range of the UInt16 type.
//    1074122 is outside the range of the UInt16 type.

Dim values() As String = { "1603", "1,603", "one", "1.6e03", "1.2e-02", _
                           "-1326", "1074122" }
Dim result As UShort

For Each value As String In values
   Try
      result = Convert.ToUInt16(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As FormatException
      Console.WriteLine("The {0} value {1} is not in a recognizable format.", _
                        value.GetType().Name, value)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the UInt16 type.", value)
   End Try   
Next
' The example displays the following output:
'    Converted the String value '1603' to the UInt16 value 1603.
'    The String value 1,603 is not in a recognizable format.
'    The String value one is not in a recognizable format.
'    The String value 1.6e03 is not in a recognizable format.
'    The String value 1.2e-02 is not in a recognizable format.
'    -1326 is outside the range of the UInt16 type.
'    1074122 is outside the range of the UInt16 type.

備註

ToUInt16(String)使用方法相當於傳遞value至 UInt16.Parse(String) 方法。 value 會使用目前文化特性的格式化慣例來解譯。

如果您不想在轉換失敗時處理例外狀況，您可以改為呼叫 UInt16.TryParse 方法。它會傳回值 Boolean ，指出轉換成功或失敗。

適用於

ToUInt16(UInt16)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

傳回指定的 16 位元不帶正負號整數；不會執行實際的轉換。

public:
 static System::UInt16 ToUInt16(System::UInt16 value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (ushort value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : uint16 -> uint16

Public Shared Function ToUInt16 (value As UShort) As UShort

參數

value: UInt16

要傳回之 16 位元不帶正負號的整數。

傳回

UInt16

value 會原封不動地傳回。

屬性: CLSCompliantAttribute

適用於

ToUInt16(UInt32)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 32 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。

public:
 static System::UInt16 ToUInt16(System::UInt32 value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (uint value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : uint32 -> uint16

Public Shared Function ToUInt16 (value As UInteger) As UShort

參數

value: UInt32

要轉換之 32 位元不帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 大於 UInt16.MaxValue。

範例

下列範例會嘗試將不帶正負號整數陣列中的每個元素轉換成不帶正負號的16位整數。

uint[] numbers = { UInt32.MinValue, 121, 340, UInt32.MaxValue };
ushort result;

foreach (uint number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    Converted the UInt32 value '0' to the UInt16 value 0.
//    Converted the UInt32 value '121' to the UInt16 value 121.
//    Converted the UInt32 value '340' to the UInt16 value 340.
//    The UInt32 value 4294967295 is outside the range of the UInt16 type.

let numbers = [| UInt32.MinValue; 121u; 340u; UInt32.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"The {number.GetType().Name} value {number} is outside the range of the UInt16 type."
                        
// The example displays the following output:
//    Converted the UInt32 value '0' to the UInt16 value 0.
//    Converted the UInt32 value '121' to the UInt16 value 121.
//    Converted the UInt32 value '340' to the UInt16 value 340.
//    The UInt32 value 4294967295 is outside the range of the UInt16 type.

Dim numbers() As UInteger = { UInt32.MinValue, 121, 340, UInt32.MaxValue }
Dim result As UShort
For Each number As UInteger In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    Converted the UInt32 value '0' to the UInt16 value 0.
'    Converted the UInt32 value '121' to the UInt16 value 121.
'    Converted the UInt32 value '340' to the UInt16 value 340.
'    The UInt32 value 4294967295 is outside the range of the UInt16 type.

適用於

ToUInt16(String, Int32)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定基底中數字的字串表示，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::String ^ value, int fromBase);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string value, int fromBase);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string? value, int fromBase);

[<System.CLSCompliant(false)>]
static member ToUInt16 : string * int -> uint16

Public Shared Function ToUInt16 (value As String, fromBase As Integer) As UShort

參數

value: String

字串，包含要轉換的數字。

fromBase: Int32

value 中數字的基底，必須是 2、8、10 或 16。

傳回

UInt16

與 value 中之數字相等的 16 位元不帶正負號的整數；如果 value 為 null，則為 0 (零)。

屬性: CLSCompliantAttribute

例外狀況

ArgumentException

fromBase 不是 2、8、10 或 16。

-或-

代表非基底 10 不帶正負號數字的value，前面會加上負號。

ArgumentOutOfRangeException

value 為 Empty。

FormatException

value 所包含的字元在 fromBase 指定的基底中不是有效數字。如果 value 中的第一個字元無效，例外狀況訊息會指出沒有數字可進行轉換；否則訊息會指出 value 包含無效的尾端字元。

OverflowException

代表非基底 10 不帶正負號數字的value，前面會加上負號。

-或-

value 代表小於 UInt16.MinValue 或大於 UInt16.MaxValue 的數位。

範例

下列範例會嘗試將數值字串陣列中的每個元素解譯為十六進位值，並將它轉換成不帶正負號的16位整數。

using System;

public class Example
{
   public static void Main()
   {
      string[] hexStrings = { "8000", "0FFF", "f000", "00A30", "D", "-13",
                              "9AC61", "GAD" };
      foreach (string hexString in hexStrings)
      {
         try {
            ushort number = Convert.ToUInt16(hexString, 16);
            Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number);
         }
         catch (FormatException) {
            Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.",
                              hexString);
         }
         catch (OverflowException) {
            Console.WriteLine("'{0}' is outside the range of an Int16.", hexString);
         }
         catch (ArgumentException) {
            Console.WriteLine("'{0}' is invalid in base 16.", hexString);
         }
      }
   }
}
// The example displays the following output:
//    Converted '8000' to 32,768.
//    Converted '0FFF' to 4,095.
//    Converted 'f000' to 61,440.
//    Converted '00A30' to 2,608.
//    Converted 'D' to 13.
//    '-13' is invalid in base 16.
//    '9AC61' is outside the range of an Int16.
//    'GAD' is not in the correct format for a hexadecimal number.

open System

let hexStrings =
    [| "8000"; "0FFF"; "f000"; "00A30"
       "D"; "-13"; "9AC61"; "GAD" |]
for hexString in hexStrings do
    try
        let number = Convert.ToUInt16(hexString, 16)
        printfn $"Converted '{hexString}' to {number:N0}."
    with
    | :? FormatException ->
        printfn $"'{hexString}' is not in the correct format for a hexadecimal number."
    | :? OverflowException ->
        printfn $"'{hexString}' is outside the range of an Int16."
    | :? ArgumentException ->
        printfn $"'{hexString}' is invalid in base 16."
// The example displays the following output:
//    Converted '8000' to 32,768.
//    Converted '0FFF' to 4,095.
//    Converted 'f000' to 61,440.
//    Converted '00A30' to 2,608.
//    Converted 'D' to 13.
//    '-13' is invalid in base 16.
//    '9AC61' is outside the range of an Int16.
//    'GAD' is not in the correct format for a hexadecimal number.

Module Example
   Public Sub Main()
      Dim hexStrings() As String = { "8000", "0FFF", "f000", "00A30", "D", _
                                     "-13", "9AC61", "GAD" }
      For Each hexString As String In hexStrings
         Try
            Dim number As UShort = Convert.ToUInt16(hexString, 16)
            Console.WriteLine("Converted '{0}' to {1:N0}.", hexString, number)
         Catch e As FormatException
            Console.WriteLine("'{0}' is not in the correct format for a hexadecimal number.", _
                              hexString)
         Catch e As OverflowException
            Console.WriteLine("'{0}' is outside the range of an Int16.", hexString)
         Catch e As ArgumentException
            Console.WriteLine("'{0}' is invalid in base 16.", hexString)
         End Try
      Next                                            
   End Sub
End Module
'    ' The example displays the following output:
'    Converted '8000' to 32,768.
'    Converted '0FFF' to 4,095.
'    Converted 'f000' to 61,440.
'    Converted '00A30' to 2,608.
'    Converted 'D' to 13.
'    '-13' is invalid in base 16.
'    '9AC61' is outside the range of an Int16.
'    'GAD' is not in the correct format for a hexadecimal number.

備註

如果 fromBase 為 16，您可以在參數所 value 指定的數位前面加上 “0x” 或 “0X”。

UInt16因為數據類型只支援不帶正負號的值，ToUInt16(String, Int32)所以方法會value假設使用不帶正負號的二進位表示法表示。換句話說，所有16位都用來表示數值，而符號位則不存在。因此，可以撰寫程序代碼，其中超出數據類型範圍的 UInt16 帶正負號整數值會 UInt16 轉換成值，而不會擲回例外狀況的方法。下列範例會 Int16.MinValue 轉換成其十六進位字串表示法，然後呼叫 ToUInt16(String, Int32) 方法。方法不會擲回例外狀況，而是會顯示訊息：「0x8000轉換成 32768」。

// Create a hexadecimal value out of range of the UInt16 type.
string value = Convert.ToString(Int16.MinValue, 16);
// Convert it back to a number.
try
{
   UInt16 number = Convert.ToUInt16(value, 16);
   Console.WriteLine("0x{0} converts to {1}.", value, number);
}
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned short integer.",
                     value);
}

// Create a hexadecimal value out of range of the UInt16 type.
let value = Convert.ToString(Int16.MinValue, 16)
// Convert it back to a number.
try
    let number = Convert.ToUInt16(value, 16)
    printfn $"0x{value} converts to {number}."
with :? OverflowException ->
    printfn $"Unable to convert '0x{value}' to an unsigned short integer."

' Create a hexadecimal value out of range of the UInt16 type.
Dim value As String = Convert.ToString(Short.MinValue, 16)
' Convert it back to a number.
Try
   Dim number As UInt16 = Convert.ToUInt16(value, 16)
   Console.WriteLine("0x{0} converts to {1}.", value, number)
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned short integer.", _
                     value)
End Try

執行二進位運算或數值轉換時，開發人員一律會負責確認方法或運算元是否使用適當的數值表示法來解譯特定值。下列範例說明一種技術，以確保方法不會不當使用二進位表示法來解譯將十六進位字串轉換成 UInt16 值時，使用兩個補碼表示法的值。此範例會判斷值是否代表帶正負號或不帶正負號的整數，同時將該值轉換為其字串表示法。當範例將值轉換成值 UInt16 時，它會檢查原始值是否為帶正負號的整數。如果是，而且如果設定其高序位 (表示原始值為負數) ，則方法會擲回例外狀況。

// Create a negative hexadecimal value out of range of the UInt16 type.
short sourceNumber = Int16.MinValue;
bool isSigned = Math.Sign((short)sourceNumber.GetType().GetField("MinValue").GetValue(null)) == -1;
string value = Convert.ToString(sourceNumber, 16);
UInt16 targetNumber;
try
{
   targetNumber = Convert.ToUInt16(value, 16);
   if (isSigned && ((targetNumber & 0x8000) != 0))
      throw new OverflowException();
   else
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber);
}
catch (OverflowException)
{
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned short integer.", value);
}
// Displays the following to the console:
//    Unable to convert '0x8000' to an unsigned short integer.

// Create a negative hexadecimal value out of range of the UInt16 type.
let sourceNumber = Int16.MinValue
let isSigned = sign (sourceNumber.GetType().GetField("MinValue").GetValue null :?> int16) = -1
let value = Convert.ToString(sourceNumber, 16)
try
    let targetNumber = Convert.ToUInt16(value, 16)
    if isSigned && targetNumber &&& 0x8000us <> 0us then
        raise (OverflowException())
    else
        printfn $"0x{value} converts to {targetNumber}."
with :? OverflowException ->
    printfn $"Unable to convert '0x{value}' to an unsigned short integer."
// Displays the following to the console:
//    Unable to convert '0x8000' to an unsigned short integer.

' Create a negative hexadecimal value out of range of the UInt16 type.
Dim sourceNumber As Short = Short.MinValue
Dim isSigned As Boolean = Math.Sign(sourceNumber.MinValue) = -1
Dim value As String = Convert.ToString(sourceNumber, 16)
Dim targetNumber As UInt16
Try
   targetNumber = Convert.ToUInt16(value, 16)
   If isSigned And ((targetNumber And &H8000) <> 0) Then
      Throw New OverflowException()
   Else 
      Console.WriteLine("0x{0} converts to {1}.", value, targetNumber)
   End If    
Catch e As OverflowException
   Console.WriteLine("Unable to convert '0x{0}' to an unsigned short integer.", _
                     value)
End Try 
' Displays the following to the console:
'    Unable to convert '0x8000' to an unsigned short integer.

適用於

ToUInt16(Object, IFormatProvider)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

使用指定之特定文化特性格式資訊，將指定之物件的值轉換為 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::Object ^ value, IFormatProvider ^ provider);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (object value, IFormatProvider provider);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (object? value, IFormatProvider? provider);

[<System.CLSCompliant(false)>]
static member ToUInt16 : obj * IFormatProvider -> uint16

Public Shared Function ToUInt16 (value As Object, provider As IFormatProvider) As UShort

參數

value: Object

實作 IConvertible 介面的物件。

provider: IFormatProvider

物件，提供特定文化特性格式資訊。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數；如果 value 為 null，則為零。

屬性: CLSCompliantAttribute

例外狀況

FormatException

value 的格式不正確。

InvalidCastException

value 未實作 IConvertible 介面。

-或-

不支援轉換。

OverflowException

value 代表小於 UInt16.MinValue 或大於 UInt16.MaxValue 的數位。

範例

下列範例會定義實 HexString 作介面的 IConvertible 類別，其設計目的是要保存16位帶正負號和16位無符號值的字串表示。類別包含 Sign 屬性，指出其十六進位值的正負號。

using System;
using System.Globalization;
using System.Text.RegularExpressions;

public enum SignBit { Negative=-1, Zero=0, Positive=1 };

public struct HexString : IConvertible
{
   private SignBit signBit;
   private string hexString;

   public SignBit Sign
   {
      set { signBit = value; }
      get { return signBit; }
   }

   public string Value
   {
      set {
         if (value.Trim().Length > 4)
            throw new ArgumentException("The string representation of a 160bit integer cannot have more than four characters.");
         else if (! Regex.IsMatch(value, "([0-9,A-F]){1,4}", RegexOptions.IgnoreCase))
            throw new ArgumentException("The hexadecimal representation of a 16-bit integer contains invalid characters.");
         else
            hexString = value;
      }
      get { return hexString; }
   }

   // IConvertible implementations.
   public TypeCode GetTypeCode() {
      return TypeCode.Object;
   }

   public bool ToBoolean(IFormatProvider provider)
   {
      return signBit != SignBit.Zero;
   }

   public byte ToByte(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is out of range of the Byte type.", Convert.ToInt16(hexString, 16)));
      else
         try {
            return Convert.ToByte(UInt16.Parse(hexString, NumberStyles.HexNumber));
         }
         catch (OverflowException e) {
            throw new OverflowException(String.Format("{0} is out of range of the UInt16 type.", Convert.ToUInt16(hexString, 16)), e);
         }
   }

   public char ToChar(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative) {
         throw new OverflowException(String.Format("{0} is out of range of the Char type.", Convert.ToInt16(hexString, 16)));
      }

      UInt16 codePoint = UInt16.Parse(this.hexString, NumberStyles.HexNumber);
      return Convert.ToChar(codePoint);
   }

   public DateTime ToDateTime(IFormatProvider provider)
   {
      throw new InvalidCastException("Hexadecimal to DateTime conversion is not supported.");
   }

   public decimal ToDecimal(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
      {
         short hexValue = Int16.Parse(hexString, NumberStyles.HexNumber);
         return Convert.ToDecimal(hexValue);
      }
      else
      {
         ushort hexValue = UInt16.Parse(hexString, NumberStyles.HexNumber);
         return Convert.ToDecimal(hexValue);
      }
   }

   public double ToDouble(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToDouble(Int16.Parse(hexString, NumberStyles.HexNumber));
      else
         return Convert.ToDouble(UInt16.Parse(hexString, NumberStyles.HexNumber));
   }

   public short ToInt16(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Int16.Parse(hexString, NumberStyles.HexNumber);
      else
         try {
            return Convert.ToInt16(UInt16.Parse(hexString, NumberStyles.HexNumber));
         }
         catch (OverflowException e) {
            throw new OverflowException(String.Format("{0} is out of range of the Int16 type.",
                                                      Convert.ToUInt16(hexString, 16)), e);
         }
   }

   public int ToInt32(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToInt32(Int16.Parse(hexString, NumberStyles.HexNumber));
      else
         return Convert.ToInt32(UInt16.Parse(hexString, NumberStyles.HexNumber));
   }

   public long ToInt64(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToInt64(Int16.Parse(hexString, NumberStyles.HexNumber));
      else
         return Int64.Parse(hexString, NumberStyles.HexNumber);
   }

   public sbyte ToSByte(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         try {
            return Convert.ToSByte(Int16.Parse(hexString, NumberStyles.HexNumber));
         }
         catch (OverflowException e) {
            throw new OverflowException(String.Format("{0} is outside the range of the SByte type.",
                                                      Int16.Parse(hexString, NumberStyles.HexNumber), e));
         }
      else
         try {
            return Convert.ToSByte(UInt16.Parse(hexString, NumberStyles.HexNumber));
         }
         catch (OverflowException e) {
            throw new OverflowException(String.Format("{0} is outside the range of the SByte type.",
                                                   UInt16.Parse(hexString, NumberStyles.HexNumber)), e);
         }
   }

   public float ToSingle(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         return Convert.ToSingle(Int16.Parse(hexString, NumberStyles.HexNumber));
      else
         return Convert.ToSingle(UInt16.Parse(hexString, NumberStyles.HexNumber));
   }

   public string ToString(IFormatProvider provider)
   {
      return "0x" + this.hexString;
   }

   public object ToType(Type conversionType, IFormatProvider provider)
   {
      switch (Type.GetTypeCode(conversionType))
      {
         case TypeCode.Boolean:
            return this.ToBoolean(null);
         case TypeCode.Byte:
            return this.ToByte(null);
         case TypeCode.Char:
            return this.ToChar(null);
         case TypeCode.DateTime:
            return this.ToDateTime(null);
         case TypeCode.Decimal:
            return this.ToDecimal(null);
         case TypeCode.Double:
            return this.ToDouble(null);
         case TypeCode.Int16:
            return this.ToInt16(null);
         case TypeCode.Int32:
            return this.ToInt32(null);
         case TypeCode.Int64:
            return this.ToInt64(null);
         case TypeCode.Object:
            if (typeof(HexString).Equals(conversionType))
               return this;
            else
               throw new InvalidCastException(String.Format("Conversion to a {0} is not supported.", conversionType.Name));
         case TypeCode.SByte:
            return this.ToSByte(null);
         case TypeCode.Single:
            return this.ToSingle(null);
         case TypeCode.String:
            return this.ToString(null);
         case TypeCode.UInt16:
            return this.ToUInt16(null);
         case TypeCode.UInt32:
            return this.ToUInt32(null);
         case TypeCode.UInt64:
            return this.ToUInt64(null);
         default:
            throw new InvalidCastException(String.Format("Conversion to {0} is not supported.", conversionType.Name));
      }
   }

   public UInt16 ToUInt16(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt16 type.",
                                                   Int16.Parse(hexString, NumberStyles.HexNumber)));
      else
         return UInt16.Parse(hexString, NumberStyles.HexNumber);
   }

   public UInt32 ToUInt32(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt32 type.",
                                                   Int16.Parse(hexString, NumberStyles.HexNumber)));
      else
         return Convert.ToUInt32(hexString, 16);
   }

   public UInt64 ToUInt64(IFormatProvider provider)
   {
      if (signBit == SignBit.Negative)
         throw new OverflowException(String.Format("{0} is outside the range of the UInt64 type.",
                                                   Int64.Parse(hexString, NumberStyles.HexNumber)));
      else
         return Convert.ToUInt64(hexString, 16);
   }
}

open System
open System.Globalization
open System.Text.RegularExpressions

type SignBit =
    | Negative = -1
    | Zero = 0
    | Positive = 1

[<Struct>]
type HexString =
    val mutable private hexString: string

    val mutable Sign: SignBit

    member this.Value
        with get () = this.hexString
        and set (value: string) =
            if value.Trim().Length > 4 then
                invalidArg "value" "The string representation of a 16 bit integer cannot have more than four characters."
            elif Regex.IsMatch(value, "([0-9,A-F]){1,4}", RegexOptions.IgnoreCase) |> not then
                invalidArg "value" "The hexadecimal representation of a 16-bit integer contains invalid characters."
            else
                this.hexString <- value

    interface IConvertible with
        // IConvertible implementations.
        member _.GetTypeCode() =
            TypeCode.Object

        member this.ToBoolean(provider: IFormatProvider) =
            this.Sign <> SignBit.Zero

        member this.ToByte(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                raise (OverflowException $"{Convert.ToInt16(this.hexString, 16)} is out of range of the Byte type.")
            else
                try
                    Convert.ToByte(UInt16.Parse(this.hexString, NumberStyles.HexNumber))
                with :? OverflowException as e ->
                    raise (OverflowException($"{Convert.ToUInt16(this.hexString, 16)} is out of range of the UInt16 type.", e) )

        member this.ToChar(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                raise (OverflowException $"{Convert.ToInt16(this.hexString, 16)} is out of range of the Char type.")

            let codePoint = UInt16.Parse(this.hexString, NumberStyles.HexNumber)
            Convert.ToChar codePoint

        member _.ToDateTime(provider: IFormatProvider) =
            raise (InvalidCastException "Hexadecimal to DateTime conversion is not supported.")

        member this.ToDecimal(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                let hexValue = Int16.Parse(this.hexString, NumberStyles.HexNumber)
                Convert.ToDecimal hexValue
            else
                let hexValue = UInt16.Parse(this.hexString, NumberStyles.HexNumber)
                Convert.ToDecimal hexValue

        member this.ToDouble(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                Convert.ToDouble(Int16.Parse(this.hexString, NumberStyles.HexNumber))
            else
                Convert.ToDouble(UInt16.Parse(this.hexString, NumberStyles.HexNumber))

        member this.ToInt16(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                Int16.Parse(this.hexString, NumberStyles.HexNumber)
            else
                try
                    Convert.ToInt16(UInt16.Parse(this.hexString, NumberStyles.HexNumber))
                with :? OverflowException as e ->
                    raise (OverflowException($"{Convert.ToUInt16(this.hexString, 16)} is out of range of the Int16 type.", e) )

        member this.ToInt32(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                Convert.ToInt32(Int16.Parse(this.hexString, NumberStyles.HexNumber))
            else
                Convert.ToInt32(UInt16.Parse(this.hexString, NumberStyles.HexNumber))

        member this.ToInt64(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                Convert.ToInt64(Int16.Parse(this.hexString, NumberStyles.HexNumber))
            else
                Int64.Parse(this.hexString, NumberStyles.HexNumber)

        member this.ToSByte(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                try
                    Convert.ToSByte(Int16.Parse(this.hexString, NumberStyles.HexNumber))
                with :? OverflowException as e ->
                    raise (OverflowException($"{Int16.Parse(this.hexString, NumberStyles.HexNumber)} is outside the range of the SByte type.", e))
            else
                try
                    Convert.ToSByte(UInt16.Parse(this.hexString, NumberStyles.HexNumber))
                with :? OverflowException as e ->
                    raise (OverflowException($"{UInt16.Parse(this.hexString, NumberStyles.HexNumber)} is outside the range of the SByte type.", e) )

        member this.ToSingle(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                Convert.ToSingle(Int16.Parse(this.hexString, NumberStyles.HexNumber))
            else
                Convert.ToSingle(UInt16.Parse(this.hexString, NumberStyles.HexNumber))

        member this.ToString(provider: IFormatProvider) =
            "0x" + this.hexString

        member this.ToType(conversionType: Type, provider: IFormatProvider) =
            let this = this :> IConvertible
            match Type.GetTypeCode conversionType with
            | TypeCode.Boolean ->
                this.ToBoolean null
            | TypeCode.Byte ->
                this.ToByte null
            | TypeCode.Char ->
                this.ToChar null
            | TypeCode.DateTime ->
                this.ToDateTime null
            | TypeCode.Decimal->
                this.ToDecimal null
            | TypeCode.Double ->
                this.ToDouble null
            | TypeCode.Int16 ->
                this.ToInt16 null
            | TypeCode.Int32 ->
                this.ToInt32 null
            | TypeCode.Int64 ->
                this.ToInt64 null
            | TypeCode.Object ->
                if typeof<HexString>.Equals conversionType then
                    this
                else
                    raise (InvalidCastException $"Conversion to a {conversionType.Name} is not supported.")
            | TypeCode.SByte ->
                this.ToSByte null
            | TypeCode.Single ->
                this.ToSingle null
            | TypeCode.String ->
                this.ToString null
            | TypeCode.UInt16 ->
                this.ToUInt16 null
            | TypeCode.UInt32 ->
                this.ToUInt32 null
            | TypeCode.UInt64 ->
                this.ToUInt64 null
            | _ ->
                raise (InvalidCastException $"Conversion to {conversionType.Name} is not supported.")

        member this.ToUInt16(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                raise (OverflowException $"{Int16.Parse(this.hexString, NumberStyles.HexNumber)} is outside the range of the UInt16 type.")
            else
                UInt16.Parse(this.hexString, NumberStyles.HexNumber)

        member this.ToUInt32(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                raise (OverflowException $"{Int16.Parse(this.hexString, NumberStyles.HexNumber)} is outside the range of the UInt32 type.")
            else
                Convert.ToUInt32(this.hexString, 16)

        member this.ToUInt64(provider: IFormatProvider) =
            if this.Sign = SignBit.Negative then
                raise (OverflowException $"{Int64.Parse(this.hexString, NumberStyles.HexNumber)} is outside the range of the UInt64 type.")
            else
                Convert.ToUInt64(this.hexString, 16)

Imports System.Globalization
Imports System.Text.RegularExpressions

Public Enum SignBit As Integer
   Positive = 1
   Zero = 0
   Negative = -1
End Enum

Public Structure HexString : Implements IConvertible
   Private signBit As SignBit
   Private hexString As String
   
   Public Property Sign As SignBit
      Set
         signBit = value
      End Set
      Get
         Return signBit
      End Get
   End Property
   
   Public Property Value As String
      Set
         If value.Trim().Length > 4 Then
            Throw New ArgumentException("The string representation of a 16-bit integer cannot have more than four characters.")
         Else If Not Regex.IsMatch(value, "([0-9,A-F]){1,4}", RegexOptions.IgnoreCase) Then
            Throw New ArgumentException("The hexadecimal representation of a 16-bit integer contains invalid characters.")             
         Else
            hexString = value
         End If   
      End Set
      Get
         Return hexString
      End Get
   End Property
   
   ' IConvertible implementations.
   Public Function GetTypeCode() As TypeCode _
                   Implements IConvertible.GetTypeCode
      Return TypeCode.Object
   End Function
   
   Public Function ToBoolean(provider As IFormatProvider) As Boolean _
                   Implements IConvertible.ToBoolean
      Return signBit <> SignBit.Zero             
   End Function 
   
   Public Function ToByte(provider As IFormatProvider) As Byte _
                   Implements IConvertible.ToByte
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is out of range of the Byte type.", Convert.ToInt16(hexString, 16))) 
      Else
         Try
            Return Convert.ToByte(Int16.Parse(hexString, NumberStyles.HexNumber))
         Catch e As OverflowException
            Throw New OverflowException(String.Format("{0} is out of range of the UInt16 type.", Convert.ToUInt16(hexString, 16)), e)
         End Try   
      End If       
   End Function
   
   Public Function ToChar(provider As IFormatProvider) As Char _
                   Implements IConvertible.ToChar
      If signBit = signBit.Negative Then 
         Throw New OverflowException(String.Format("{0} is out of range of the Char type.", Convert.ToInt16(hexString, 16)))
      End If
      
      Dim codePoint As UInt16 = UInt16.Parse(Me.hexString, NumberStyles.HexNumber)
      Return Convert.ToChar(codePoint)
   End Function 
   
   Public Function ToDateTime(provider As IFormatProvider) As Date _
                   Implements IConvertible.ToDateTime
      Throw New InvalidCastException("Hexadecimal to DateTime conversion is not supported.")
   End Function
   
   Public Function ToDecimal(provider As IFormatProvider) As Decimal _
                   Implements IConvertible.ToDecimal
      If signBit = signBit.Negative Then
         Dim hexValue As Short = Int16.Parse(hexString, NumberStyles.HexNumber)
         Return Convert.ToDecimal(hexValue)
      Else
         Dim hexValue As UShort = UInt16.Parse(hexString, NumberStyles.HexNumber)
         Return Convert.ToDecimal(hexValue)
      End If
   End Function
   
   Public Function ToDouble(provider As IFormatProvider) As Double _
                   Implements IConvertible.ToDouble
      If signBit = signBit.Negative Then
         Return Convert.ToDouble(Int16.Parse(hexString, NumberStyles.HexNumber))
      Else
         Return Convert.ToDouble(UInt16.Parse(hexString, NumberStyles.HexNumber))
      End If   
   End Function   
   
   Public Function ToInt16(provider As IFormatProvider) As Int16 _
                   Implements IConvertible.ToInt16
      If signBit = SignBit.Negative Then
         Return Int16.Parse(hexString, NumberStyles.HexNumber)
      Else
         Try
            Return Convert.ToInt16(UInt16.Parse(hexString, NumberStyles.HexNumber))
         Catch e As OverflowException
            Throw New OverflowException(String.Format("{0} is out of range of the Int16 type.", Convert.ToUInt16(hexString, 16)), e)
         End Try
      End If   
   End Function
   
   Public Function ToInt32(provider As IFormatProvider) As Int32 _
                   Implements IConvertible.ToInt32
      If signBit = SignBit.Negative Then
         Return Convert.ToInt32(Int16.Parse(hexString, NumberStyles.HexNumber))
      Else
         Return Convert.ToInt32(UInt16.Parse(hexString, NumberStyles.HexNumber))
      End If   
   End Function
   
   Public Function ToInt64(provider As IFormatProvider) As Int64 _
                   Implements IConvertible.ToInt64
      If signBit = signBit.Negative Then
         Return Convert.ToInt64(Int16.Parse(hexString, NumberStyles.HexNumber))
      Else
         Return Int64.Parse(hexString, NumberStyles.HexNumber)
      End If   
   End Function
   
   Public Function ToSByte(provider As IFormatProvider) As SByte _
                   Implements IConvertible.ToSByte
      If signBit = signBit.Negative Then
         Try
            Return Convert.ToSByte(Int16.Parse(hexString, NumberStyles.HexNumber))
         Catch e As OverflowException
            Throw New OverflowException(String.Format("{0} is outside the range of the SByte type.", _
                                                      Int16.Parse(hexString, NumberStyles.HexNumber), e))
         End Try
      Else
         Try
            Return Convert.ToSByte(UInt16.Parse(hexString, NumberStyles.HexNumber))
         Catch e As OverflowException
            Throw New OverflowException(String.Format("{0} is outside the range of the SByte type.", _
                                                    UInt16.Parse(hexString, NumberStyles.HexNumber)), e)
         End Try   
      End If
   End Function

   Public Function ToSingle(provider As IFormatProvider) As Single _
                   Implements IConvertible.ToSingle
      If signBit = signBit.Negative Then
         Return Convert.ToSingle(Int16.Parse(hexString, NumberStyles.HexNumber))
      Else
         Return Convert.ToSingle(UInt16.Parse(hexString, NumberStyles.HexNumber))
      End If   
   End Function

   Public Overloads Function ToString(provider As IFormatProvider) As String _
                   Implements IConvertible.ToString
      Return "0x" & Me.hexString
   End Function
   
   Public Function ToType(conversionType As Type, provider As IFormatProvider) As Object _
                   Implements IConvertible.ToType
      Select Case Type.GetTypeCode(conversionType)
         Case TypeCode.Boolean 
            Return Me.ToBoolean(Nothing)
         Case TypeCode.Byte
            Return Me.ToByte(Nothing)
         Case TypeCode.Char
            Return Me.ToChar(Nothing)
         Case TypeCode.DateTime
            Return Me.ToDateTime(Nothing)
         Case TypeCode.Decimal
            Return Me.ToDecimal(Nothing)
         Case TypeCode.Double
            Return Me.ToDouble(Nothing)
         Case TypeCode.Int16
            Return Me.ToInt16(Nothing)
         Case TypeCode.Int32
            Return Me.ToInt32(Nothing)
         Case TypeCode.Int64
            Return Me.ToInt64(Nothing)
         Case TypeCode.Object
            If GetType(HexString).Equals(conversionType) Then
               Return Me
            Else
               Throw New InvalidCastException(String.Format("Conversion to a {0} is not supported.", conversionType.Name))
            End If 
         Case TypeCode.SByte
            Return Me.ToSByte(Nothing)
         Case TypeCode.Single
            Return Me.ToSingle(Nothing)
         Case TypeCode.String
            Return Me.ToString(Nothing)
         Case TypeCode.UInt16
            Return Me.ToUInt16(Nothing)
         Case TypeCode.UInt32
            Return Me.ToUInt32(Nothing)
         Case TypeCode.UInt64
            Return Me.ToUInt64(Nothing)   
         Case Else
            Throw New InvalidCastException(String.Format("Conversion to {0} is not supported.", conversionType.Name))   
      End Select
   End Function
   
   Public Function ToUInt16(provider As IFormatProvider) As UInt16 _
                   Implements IConvertible.ToUInt16
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt16 type.", _
                                                   Int16.Parse(hexString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt16(hexString, 16)
      End If   
   End Function

   Public Function ToUInt32(provider As IFormatProvider) As UInt32 _
                   Implements IConvertible.ToUInt32
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt32 type.", _
                                                   Int16.Parse(hexString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt32(hexString, 16)
      End If   
   End Function
   
   Public Function ToUInt64(provider As IFormatProvider) As UInt64 _
                   Implements IConvertible.ToUInt64
      If signBit = signBit.Negative Then
         Throw New OverflowException(String.Format("{0} is outside the range of the UInt64 type.", _
                                                   Int16.Parse(hexString, NumberStyles.HexNumber)))
      Else
         Return Convert.ToUInt64(hexString, 16)
      End If   
   End Function
   
End Structure

下列範例顯示 ToUInt16(Object, IFormatProvider) 呼叫將對象當做參數傳遞 HexString 的方法，接著會呼叫 IConvertible.ToUInt16 類別的實作 HexString 。

public class Example
{
   public static void Main()
   {
      ushort positiveValue = 32000;
      short negativeValue = -1;

      HexString positiveString = new HexString();
      positiveString.Sign = (SignBit) Math.Sign(positiveValue);
      positiveString.Value = positiveValue.ToString("X2");

      HexString negativeString = new HexString();
      negativeString.Sign = (SignBit) Math.Sign(negativeValue);
      negativeString.Value = negativeValue.ToString("X2");

      try {
         Console.WriteLine("0x{0} converts to {1}.", positiveString.Value, Convert.ToUInt16(positiveString));
      }
      catch (OverflowException) {
         Console.WriteLine("{0} is outside the range of the UInt16 type.",
                           Int16.Parse(negativeString.Value, NumberStyles.HexNumber));
      }

      try {
         Console.WriteLine("0x{0} converts to {1}.", negativeString.Value, Convert.ToUInt16(negativeString));
      }
      catch (OverflowException) {
         Console.WriteLine("{0} is outside the range of the UInt16 type.",
                           Int16.Parse(negativeString.Value, NumberStyles.HexNumber));
      }
   }
}
// The example displays the following output:
//       0x7D00 converts to 32000.
//       -1 is outside the range of the UInt16 type.

let positiveValue = 32000us
let negativeValue = -1s

let mutable positiveString = HexString()
positiveString.Sign <- Math.Sign positiveValue |> enum
positiveString.Value <- positiveValue.ToString "X2"

let mutable negativeString = HexString()
negativeString.Sign <- sign negativeValue |> enum
negativeString.Value <- negativeValue.ToString "X2"

try
    printfn $"0x{positiveString.Value} converts to {Convert.ToUInt16 positiveString}."
with :? OverflowException ->
    printfn $"{Int16.Parse(negativeString.Value, NumberStyles.HexNumber)} is outside the range of the UInt16 type."

try
    printfn $"0x{negativeString.Value} converts to {Convert.ToUInt16 negativeString}."
with :? OverflowException ->
    printfn $"{Int16.Parse(negativeString.Value, NumberStyles.HexNumber)} is outside the range of the UInt16 type."
// The example displays the following output:
//       0x7D00 converts to 32000.
//       -1 is outside the range of the UInt16 type.

Module Example
   Public Sub Main()
      Dim positiveValue As UInt16 = 32000
      Dim negativeValue As Int16 = -1
      
      
      Dim positiveString As New HexString()
      positiveString.Sign = CType(Math.Sign(positiveValue), SignBit)
      positiveString.Value = positiveValue.ToString("X4")
      
      Dim negativeString As New HexString()
      negativeString.Sign = CType(Math.Sign(negativeValue), SignBit)
      negativeString.Value = negativeValue.ToString("X4")
      
      Try
         Console.WriteLine("0x{0} converts to {1}.", positiveString.Value, Convert.ToUInt16(positiveString))
      Catch e As OverflowException
         Console.WriteLine("{0} is outside the range of the UInt16 type.", _
                           Int16.Parse(positiveString.Value, NumberStyles.HexNumber))
      End Try

      Try
         Console.WriteLine("0x{0} converts to {1}.", negativeString.Value, Convert.ToUInt16(negativeString))
      Catch e As OverflowException
         Console.WriteLine("{0} is outside the range of the UInt16 type.", _
                           Int16.Parse(negativeString.Value, NumberStyles.HexNumber))
      End Try   
   End Sub
End Module
' The example dosplays the following output:
'       0x7D00 converts to 32000.
'       -1 is outside the range of the UInt16 type.

備註

傳回值是叫用 IConvertible.ToUInt16 基礎類型 value之方法的結果。

provider 可讓使用者指定有關內容 value的文化特性特定轉換資訊。例如，如果 value 是 String 代表數位的， provider 可能會提供用來表示該數位之表示法的文化特性特定資訊。

基底類型會忽略 provider;不過，如果 value 是實作 IConvertible 介面的使用者定義型別，可以使用參數。

適用於

ToUInt16(String, IFormatProvider)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

使用指定之特定文化特性格式資訊，將指定之數字的字串表示轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::String ^ value, IFormatProvider ^ provider);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string value, IFormatProvider provider);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (string? value, IFormatProvider? provider);

[<System.CLSCompliant(false)>]
static member ToUInt16 : string * IFormatProvider -> uint16

Public Shared Function ToUInt16 (value As String, provider As IFormatProvider) As UShort

參數

value: String

字串，包含要轉換的數字。

provider: IFormatProvider

物件，提供特定文化特性格式資訊。

傳回

UInt16

與 value 中之數字相等的 16 位元不帶正負號的整數；如果 value 為 null，則為 0 (零)。

屬性: CLSCompliantAttribute

例外狀況

FormatException

value 不是由後面接著一連串數字 (0 到 9) 的任意符號所組成。

OverflowException

value 代表小於 UInt16.MinValue 或大於 UInt16.MaxValue 的數位。

範例

下列範例會定義自定義 NumberFormatInfo 物件，將字串「pos」辨識為正負號，並將字串「neg」定義為負號。然後，它會嘗試使用這個提供者和 NumberFormatInfo 不變異文化特性的提供者，將數值字串陣列的每個元素轉換成整數。

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      // Create a NumberFormatInfo object and set several of its
      // properties that apply to numbers.
      NumberFormatInfo provider = new NumberFormatInfo();
      provider.PositiveSign = "pos ";
      provider.NegativeSign = "neg ";

      // Define an array of strings to convert to UInt16 values.
      string[] values= { "34567", "+34567", "pos 34567", "34567.",
                         "34567.", "65535", "65535", "65535" };

      foreach (string value in values)
      {
         Console.Write("{0,-12:}  -->  ", value);
         try {
            Console.WriteLine("{0,17}", Convert.ToUInt16(value, provider));
         }
         catch (FormatException e) {
            Console.WriteLine("{0,17}", e.GetType().Name);
         }
      }
   }
}
// The example displays the following output:
//       34567         -->              34567
//       +34567        -->    FormatException
//       pos 34567     -->              34567
//       34567.        -->    FormatException
//       34567.        -->    FormatException
//       65535         -->              65535
//       65535         -->              65535
//       65535         -->              65535

open System
open System.Globalization

// Create a NumberFormatInfo object and set several of its
// properties that apply to numbers.
let provider = NumberFormatInfo()
provider.PositiveSign <- "pos "
provider.NegativeSign <- "neg "

// Define an array of strings to convert to UInt16 values.
let values =
    [| "34567"; "+34567"; "pos 34567"; "34567."
       "34567."; "65535"; "65535"; "65535" |]

for value in values do
    printf $"{value,-12}  -->  "
    try
        printfn $"{Convert.ToUInt16(value, provider),17}"
    with :? FormatException as e ->
        printfn $"{e.GetType().Name,17}"
// The example displays the following output:
//       34567         -->              34567
//       +34567        -->    FormatException
//       pos 34567     -->              34567
//       34567.        -->    FormatException
//       34567.        -->    FormatException
//       65535         -->              65535
//       65535         -->              65535
//       65535         -->              65535

Imports System.Globalization

Module Example
   Public Sub Main()
      ' Create a NumberFormatInfo object and set several of its
      ' properties that apply to numbers.
      Dim provider As New NumberFormatInfo()
      provider.PositiveSign = "pos "
      provider.NegativeSign = "neg "

      ' Define an array of strings to convert to UInt16 values.
      Dim values() As String = { "34567", "+34567", "pos 34567", _
                                 "34567.", "34567.", "65535", _
                                 "65535", "65535" }         

      For Each value As String In values
         Console.Write("{0,-12:}  -->  ", value)
         Try
            Console.WriteLine("{0,17}", Convert.ToUInt16(value, provider))
         Catch e As FormatException       
            Console.WriteLine("{0,17}", e.GetType().Name)
         End Try     
      Next
    End Sub 
End Module 
' The example displays the following output:
'       34567         -->              34567
'       +34567        -->    FormatException
'       pos 34567     -->              34567
'       34567.        -->    FormatException
'       34567.        -->    FormatException
'       65535         -->              65535
'       65535         -->              65535
'       65535         -->              65535

備註

傳回值是在上value叫UInt16.Parse用的結果。

providerIFormatProvider是取得 NumberFormatInfo 對象的實例。物件 NumberFormatInfo 提供有關格式 value的文化特性特定資訊。如果 provider 為 null， NumberFormatInfo 則會使用目前文化特性的。

如果您不想在轉換失敗時處理例外狀況，您可以改為呼叫 UInt16.TryParse 方法。它會傳回值 Boolean ，指出轉換成功或失敗。

適用於

ToUInt16(Single)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定之單精確度浮點數的值，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(float value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (float value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : single -> uint16

Public Shared Function ToUInt16 (value As Single) As UShort

參數

value: Single

要轉換的單精確度浮點數。

傳回

UInt16

value，四捨五入為最接近的 16 位元不帶正負號整數。如果 value 介於兩個整數正中間時，則傳回偶數；也就是 4.5 會轉換為 4，5.5 會轉換為 6。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零或大於 UInt16.MaxValue。

範例

下列範例會將值陣列 String 中的每個項目轉換成不帶正負號的16位整數。

float[] numbers = { Single.MinValue, -1.38e10f, -1023.299f, -12.98f,
                   0f, 9.113e-16f, 103.919f, 17834.191f, Single.MaxValue };
ushort result;

foreach (float number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the UInt16 type.", number);
   }
}
// The example displays the following output:
//    -3.402823E+38 is outside the range of the UInt16 type.
//    -1.38E+10 is outside the range of the UInt16 type.
//    -1023.299 is outside the range of the UInt16 type.
//    -12.98 is outside the range of the UInt16 type.
//    Converted the Single value '0' to the UInt16 value 0.
//    Converted the Single value '9.113E-16' to the UInt16 value 0.
//    Converted the Single value '103.919' to the UInt16 value 104.
//    Converted the Single value '17834.19' to the UInt16 value 17834.
//    3.402823E+38 is outside the range of the UInt16 type.

let numbers = 
    [| Single.MinValue; -1.38e10f; -1023.299f; -12.98f
       0f; 9.113e-16f; 103.919f; 17834.191f; Single.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"{number} is outside the range of the UInt16 type."
// The example displays the following output:
//    -3.402823E+38 is outside the range of the UInt16 type.
//    -1.38E+10 is outside the range of the UInt16 type.
//    -1023.299 is outside the range of the UInt16 type.
//    -12.98 is outside the range of the UInt16 type.
//    Converted the Single value '0' to the UInt16 value 0.
//    Converted the Single value '9.113E-16' to the UInt16 value 0.
//    Converted the Single value '103.919' to the UInt16 value 104.
//    Converted the Single value '17834.19' to the UInt16 value 17834.
//    3.402823E+38 is outside the range of the UInt16 type.

Dim values() As Single = { Single.MinValue, -1.38e10, -1023.299, -12.98, _
                           0, 9.113e-16, 103.919, 17834.191, Single.MaxValue }
Dim result As UShort

For Each value As Single In values
   Try
      result = Convert.ToUInt16(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the UInt16 type.", value)
   End Try   
Next                                 
' The example displays the following output:
'    -3.402823E+38 is outside the range of the UInt16 type.
'    -1.38E+10 is outside the range of the UInt16 type.
'    -1023.299 is outside the range of the UInt16 type.
'    -12.98 is outside the range of the UInt16 type.
'    Converted the Single value '0' to the UInt16 value 0.
'    Converted the Single value '9.113E-16' to the UInt16 value 0.
'    Converted the Single value '103.919' to the UInt16 value 104.
'    Converted the Single value '17834.19' to the UInt16 value 17834.
'    3.402823E+38 is outside the range of the UInt16 type.

另請參閱

Single
Round

適用於

ToUInt16(UInt64)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 64 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。

public:
 static System::UInt16 ToUInt16(System::UInt64 value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (ulong value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : uint64 -> uint16

Public Shared Function ToUInt16 (value As ULong) As UShort

參數

value: UInt64

要轉換之 64 位元不帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 大於 UInt16.MaxValue。

範例

下列範例會嘗試將不帶正負號長整數陣列中的每個項目轉換為不帶正負號的16位整數。

ulong[] numbers = { UInt64.MinValue, 121, 340, UInt64.MaxValue };
ushort result;

foreach (ulong number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    Converted the UInt64 value '0' to the UInt16 value 0.
//    Converted the UInt64 value '121' to the UInt16 value 121.
//    Converted the UInt64 value '340' to the UInt16 value 340.
//    The UInt64 value 18446744073709551615 is outside the range of the UInt16 type.

let numbers = [| UInt64.MinValue; 121uL; 340uL; UInt64.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"The {number.GetType().Name} value {number} is outside the range of the UInt16 type."
// The example displays the following output:
//    Converted the UInt64 value '0' to the UInt16 value 0.
//    Converted the UInt64 value '121' to the UInt16 value 121.
//    Converted the UInt64 value '340' to the UInt16 value 340.
//    The UInt64 value 18446744073709551615 is outside the range of the UInt16 type.

Dim numbers() As ULong = { UInt64.MinValue, 121, 340, UInt64.MaxValue }
Dim result As UShort
For Each number As ULong In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    Converted the UInt64 value '0' to the UInt16 value 0.
'    Converted the UInt64 value '121' to the UInt16 value 121.
'    Converted the UInt64 value '340' to the UInt16 value 340.
'    The UInt64 value 18446744073709551615 is outside the range of the UInt16 type.

適用於

ToUInt16(SByte)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 8 位元帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。

public:
 static System::UInt16 ToUInt16(System::SByte value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (sbyte value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : sbyte -> uint16

Public Shared Function ToUInt16 (value As SByte) As UShort

參數

value: SByte

要轉換的 8 位元帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零。

範例

下列範例會將帶正負號位元組陣列中的每個項目轉換成不帶正負號的16位整數。

sbyte[] numbers = { SByte.MinValue, -1, 0, 10, SByte.MaxValue };
ushort result;

foreach (sbyte number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("{0} is outside the range of the UInt16 type.", number);
   }
}
// The example displays the following output:
//    -128 is outside the range of the UInt16 type.
//    -1 is outside the range of the UInt16 type.
//    Converted the SByte value '0' to the UInt16 value 0.
//    Converted the SByte value '10' to the UInt16 value 10.
//    Converted the SByte value '127' to the UInt16 value 127.

let numbers = [| SByte.MinValue; -1y; 0y; 10y; SByte.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"{number} is outside the range of the UInt16 type."
// The example displays the following output:
//    -128 is outside the range of the UInt16 type.
//    -1 is outside the range of the UInt16 type.
//    Converted the SByte value '0' to the UInt16 value 0.
//    Converted the SByte value '10' to the UInt16 value 10.
//    Converted the SByte value '127' to the UInt16 value 127.

Dim numbers() As SByte = { SByte.MinValue, -1, 0, 10, SByte.MaxValue }
Dim result As UShort

For Each number As SByte In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the UInt16 type.", number)
   End Try
Next
' The example displays the following output:
'    -128 is outside the range of the UInt16 type.
'    -1 is outside the range of the UInt16 type.
'    Converted the SByte value '0' to the UInt16 value 0.
'    Converted the SByte value '10' to the UInt16 value 10.
'    Converted the SByte value '127' to the UInt16 value 127.

適用於

ToUInt16(Char)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 Unicode 字元值轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(char value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (char value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : char -> uint16

Public Shared Function ToUInt16 (value As Char) As UShort

參數

value: Char

要轉換的 Unicode 字元。

傳回

UInt16

等於 value 的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

範例

下列範例會將字元陣列中的每個項目轉換成不帶正負號的16位整數。

char[] chars = { 'a', 'z', '\x0007', '\x03FF',
                 '\x7FFF', '\xFFFE' };
ushort result;

foreach (char ch in chars)
{
   try {
      result = Convert.ToUInt16(ch);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        ch.GetType().Name, ch,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("Unable to convert u+{0} to a UInt16.",
                        ((int)ch).ToString("X4"));
   }
}
// The example displays the following output:
//    Converted the Char value 'a' to the UInt16 value 97.
//    Converted the Char value 'z' to the UInt16 value 122.
//    Converted the Char value '' to the UInt16 value 7.
//    Converted the Char value '?' to the UInt16 value 1023.
//    Converted the Char value '?' to the UInt16 value 32767.
//    Converted the Char value '?' to the UInt16 value 65534.

let chars = 
    [| 'a'; 'z'; '\u0007'; '\u03FF'; '\u7FFF'; '\uFFFE' |]

for ch in chars do
    try
        let result = Convert.ToUInt16 ch
        printfn $"Converted the {ch.GetType().Name} value '{ch}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"Unable to convert u+{int ch:X4} to a UInt16."
// The example displays the following output:
//    Converted the Char value 'a' to the UInt16 value 97.
//    Converted the Char value 'z' to the UInt16 value 122.
//    Converted the Char value '' to the UInt16 value 7.
//    Converted the Char value '?' to the UInt16 value 1023.
//    Converted the Char value '?' to the UInt16 value 32767.
//    Converted the Char value '?' to the UInt16 value 65534.

Dim chars() As Char = { "a"c, "z"c, ChrW(7), ChrW(1023), _
                        ChrW(Short.MaxValue), ChrW(&hFFFE) }
Dim result As UShort
                        
For Each ch As Char in chars
   result = Convert.ToUInt16(ch)
   Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                     ch.GetType().Name, ch, _
                     result.GetType().Name, result)
Next   
' The example displays the following output:
'    Converted the Char value 'a' to the UInt16 value 97.
'    Converted the Char value 'z' to the UInt16 value 122.
'    Converted the Char value '' to the UInt16 value 7.
'    Converted the Char value '?' to the UInt16 value 1023.
'    Converted the Char value '?' to the UInt16 value 32767.
'    Converted the Char value '?' to the UInt16 value 65534.

適用於

ToUInt16(Int64)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 64 位元帶正負號的整數值轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(long value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (long value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : int64 -> uint16

Public Shared Function ToUInt16 (value As Long) As UShort

參數

value: Int64

要轉換的 64 位元帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零或大於 UInt16.MaxValue。

範例

下列範例會將長整數數位中的每個項目轉換成不帶正負號的16位整數。

long[] numbers = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue };
ushort result;

foreach (long number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    The Int64 value -9223372036854775808 is outside the range of the UInt16 type.
//    The Int64 value -1 is outside the range of the UInt16 type.
//    Converted the Int64 value '0' to the UInt16 value 0.
//    Converted the Int64 value '121' to the UInt16 value 121.
//    Converted the Int64 value '340' to the UInt16 value 340.
//    The Int64 value 9223372036854775807 is outside the range of the UInt16 type.

let numbers = [| Int64.MinValue; -1; 0; 121; 340; Int64.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn "The {number.GetType().Name} value {number} is outside the range of the UInt16 type."
// The example displays the following output:
//    The Int64 value -9223372036854775808 is outside the range of the UInt16 type.
//    The Int64 value -1 is outside the range of the UInt16 type.
//    Converted the Int64 value '0' to the UInt16 value 0.
//    Converted the Int64 value '121' to the UInt16 value 121.
//    Converted the Int64 value '340' to the UInt16 value 340.
//    The Int64 value 9223372036854775807 is outside the range of the UInt16 type.

Dim numbers() As Long = { Int64.MinValue, -1, 0, 121, 340, Int64.MaxValue }
Dim result As UShort
For Each number As Long In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    The Int64 value -9223372036854775808 is outside the range of the UInt16 type.
'    The Int64 value -1 is outside the range of the UInt16 type.
'    Converted the Int64 value '0' to the UInt16 value 0.
'    Converted the Int64 value '121' to the UInt16 value 121.
'    Converted the Int64 value '340' to the UInt16 value 340.
'    The Int64 value 9223372036854775807 is outside the range of the UInt16 type.

適用於

ToUInt16(Int32)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 32 位元帶正負號的整數值轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(int value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (int value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : int -> uint16

Public Shared Function ToUInt16 (value As Integer) As UShort

參數

value: Int32

要轉換的 32 位元帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零或大於 UInt16.MaxValue。

範例

下列範例會將整數陣列中的每個項目轉換成不帶正負號的16位整數。

int[] numbers = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue };
ushort result;

foreach (int number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    The Int32 value -2147483648 is outside the range of the UInt16 type.
//    The Int32 value -1 is outside the range of the UInt16 type.
//    Converted the Int32 value '0' to the UInt16 value 0.
//    Converted the Int32 value '121' to the UInt16 value 121.
//    Converted the Int32 value '340' to the UInt16 value 340.
//    The Int32 value 2147483647 is outside the range of the UInt16 type.

let numbers = [| Int32.MinValue; -1; 0; 121; 340; Int32.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn "The {number.GetType().Name} value {number} is outside the range of the UInt16 type."
                        
// The example displays the following output:
//    The Int32 value -2147483648 is outside the range of the UInt16 type.
//    The Int32 value -1 is outside the range of the UInt16 type.
//    Converted the Int32 value '0' to the UInt16 value 0.
//    Converted the Int32 value '121' to the UInt16 value 121.
//    Converted the Int32 value '340' to the UInt16 value 340.
//    The Int32 value 2147483647 is outside the range of the UInt16 type.

Dim numbers() As Integer = { Int32.MinValue, -1, 0, 121, 340, Int32.MaxValue }
Dim result As UShort

For Each number As Integer In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    The Int32 value -2147483648 is outside the range of the UInt16 type.
'    The Int32 value -1 is outside the range of the UInt16 type.
'    Converted the Int32 value '0' to the UInt16 value 0.
'    Converted the Int32 value '121' to the UInt16 value 121.
'    Converted the Int32 value '340' to the UInt16 value 340.
'    The Int32 value 2147483647 is outside the range of the UInt16 type.

適用於

ToUInt16(Int16)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 16 位元帶正負號整數的值，轉換為相等的 16 位元不帶正負號整數。

public:
 static System::UInt16 ToUInt16(short value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (short value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : int16 -> uint16

Public Shared Function ToUInt16 (value As Short) As UShort

參數

value: Int16

要轉換的 16 位元帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零。

範例

下列範例會嘗試將16位整數陣列中的每個項目轉換為不帶正負號的16位整數。

short[] numbers = { Int16.MinValue, -132, 0, 121, 16103, Int16.MaxValue  };
ushort result;

foreach (short number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        number.GetType().Name, number);
   }
}
// The example displays the following output:
//    The Int16 value -32768 is outside the range of the UInt16 type.
//    The Int16 value -132 is outside the range of the UInt16 type.
//    Converted the Int16 value '0' to the UInt16 value 0.
//    Converted the Int16 value '121' to the UInt16 value 121.
//    Converted the Int16 value '16103' to the UInt16 value 16103.
//    Converted the Int16 value '32767' to the UInt16 value 32767.

let numbers = [| Int16.MinValue; -132s; 0s; 121s; 16103s; Int16.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"The {number.GetType().Name} value {number} is outside the range of the UInt16 type."
// The example displays the following output:
//    The Int16 value -32768 is outside the range of the UInt16 type.
//    The Int16 value -132 is outside the range of the UInt16 type.
//    Converted the Int16 value '0' to the UInt16 value 0.
//    Converted the Int16 value '121' to the UInt16 value 121.
//    Converted the Int16 value '16103' to the UInt16 value 16103.
//    Converted the Int16 value '32767' to the UInt16 value 32767.

Dim numbers() As Short = { Int16.MinValue, -132, 0, 121, 16103, Int16.MaxValue }
Dim result As UShort

For Each number As Short In numbers
   Try
      result = Convert.ToUInt16(number)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        number.GetType().Name, number, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                        number.GetType().Name, number)
   End Try
Next
' The example displays the following output:
'    The Int16 value -32768 is outside the range of the UInt16 type.
'    The Int16 value -132 is outside the range of the UInt16 type.
'    Converted the Int16 value '0' to the UInt16 value 0.
'    Converted the Int16 value '121' to the UInt16 value 121.
'    Converted the Int16 value '16103' to the UInt16 value 16103.
'    Converted the Int16 value '32767' to the UInt16 value 32767.

適用於

ToUInt16(Decimal)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定之十進位數字的值，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::Decimal value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (decimal value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : decimal -> uint16

Public Shared Function ToUInt16 (value As Decimal) As UShort

參數

value: Decimal

要轉換的十進位數字。

傳回

UInt16

value，四捨五入為最接近的 16 位元不帶正負號整數。如果 value 介於兩個整數正中間時，則傳回偶數；也就是 4.5 會轉換為 4，5.5 會轉換為 6。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零或大於 UInt16.MaxValue。

範例

下列範例會將值陣列 Decimal 中的每個項目轉換成不帶正負號的16位整數。

decimal[] numbers = { Decimal.MinValue, -1034.23m, -12m, 0m, 147m,
                            9214.16m, Decimal.MaxValue };
ushort result;

foreach (decimal number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException)
   {
      Console.WriteLine("{0} is outside the range of the UInt16 type.",
                        number);
   }
}
// The example displays the following output:
//    -79228162514264337593543950335 is outside the range of the UInt16 type.
//    -1034.23 is outside the range of the UInt16 type.
//    -12 is outside the range of the UInt16 type.
//    Converted the Decimal value '0' to the UInt16 value 0.
//    Converted the Decimal value '147' to the UInt16 value 147.
//    Converted the Decimal value '9214.16' to the UInt16 value 9214.
//    79228162514264337593543950335 is outside the range of the UInt16 type.

let numbers = 
    [| Decimal.MinValue; -1034.23m; -12m; 0m; 147m; 9214.16m; Decimal.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"{number} is outside the range of the UInt16 type."
// The example displays the following output:
//    -79228162514264337593543950335 is outside the range of the UInt16 type.
//    -1034.23 is outside the range of the UInt16 type.
//    -12 is outside the range of the UInt16 type.
//    Converted the Decimal value '0' to the UInt16 value 0.
//    Converted the Decimal value '147' to the UInt16 value 147.
//    Converted the Decimal value '9214.16' to the UInt16 value 9214.
//    79228162514264337593543950335 is outside the range of the UInt16 type.

Dim values() As Decimal = { Decimal.MinValue, -1034.23d, -12d, 0d, 147d, _
                            9214.16d, Decimal.MaxValue }
Dim result As UShort

For Each value As Decimal In values
   Try
      result = Convert.ToUInt16(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the UInt16 type.", _
                        value)
   End Try   
Next                                  
' The example displays the following output:
'    -79228162514264337593543950335 is outside the range of the UInt16 type.
'    -1034.23 is outside the range of the UInt16 type.
'    -12 is outside the range of the UInt16 type.
'    Converted the Decimal value '0' to the UInt16 value 0.
'    Converted the Decimal value '147' to the UInt16 value 147.
'    Converted the Decimal value '9214.16' to the UInt16 value 9214.
'    79228162514264337593543950335 is outside the range of the UInt16 type.

另請參閱

Round

適用於

ToUInt16(DateTime)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

呼叫這個方法一律會擲回 InvalidCastException。

public:
 static System::UInt16 ToUInt16(DateTime value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (DateTime value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : DateTime -> uint16

Public Shared Function ToUInt16 (value As DateTime) As UShort

參數

value: DateTime

要轉換的日期和時間值。

傳回

UInt16

不支援此轉換。沒有傳回值。

屬性: CLSCompliantAttribute

例外狀況

InvalidCastException

不支援此轉換。

適用於

ToUInt16(Byte)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的 8 位元不帶正負號整數的值，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::Byte value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (byte value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : byte -> uint16

Public Shared Function ToUInt16 (value As Byte) As UShort

參數

value: Byte

要轉換之 8 位元不帶正負號的整數。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數。

屬性: CLSCompliantAttribute

範例

下列範例會將位元組陣列中的每個項目轉換成不帶正負號的16位整數。

byte[] bytes = { Byte.MinValue, 14, 122, Byte.MaxValue};
ushort result;

foreach (byte byteValue in bytes)
{
   result = Convert.ToUInt16(byteValue);
   Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                     byteValue.GetType().Name, byteValue,
                     result.GetType().Name, result);
}
// The example displays the following output:
//       Converted the Byte value '0' to the UInt16 value 0.
//       Converted the Byte value '14' to the UInt16 value 14.
//       Converted the Byte value '122' to the UInt16 value 122.
//       Converted the Byte value '255' to the UInt16 value 255.

let bytes = [| Byte.MinValue; 14uy; 122uy; Byte.MaxValue |]

for byteValue in bytes do
    let result = Convert.ToUInt16 byteValue
    printfn $"Converted the {byteValue.GetType().Name} value '{byteValue}' to the {result.GetType().Name} value {result}."
// The example displays the following output:
//       Converted the Byte value '0' to the UInt16 value 0.
//       Converted the Byte value '14' to the UInt16 value 14.
//       Converted the Byte value '122' to the UInt16 value 122.
//       Converted the Byte value '255' to the UInt16 value 255.

Dim bytes() As Byte = { Byte.MinValue, 14, 122, Byte.MaxValue}
Dim result As UShort

For Each number As Byte In bytes
   result = Convert.ToUInt16(number)
   Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                     number.GetType().Name, number, _
                     result.GetType().Name, result)
Next
' The example displays the following output:
'    Converted the Byte value '0' to the UInt16 value 0.
'    Converted the Byte value '14' to the UInt16 value 14.
'    Converted the Byte value '122' to the UInt16 value 122.
'    Converted the Byte value '255' to the UInt16 value 255.

適用於

ToUInt16(Boolean)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定的布林值轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(bool value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (bool value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : bool -> uint16

Public Shared Function ToUInt16 (value As Boolean) As UShort

參數

value: Boolean

要轉換的布林值。

傳回

UInt16

如果 value 為 true，則為數字 1，否則為 0。

屬性: CLSCompliantAttribute

範例

下列範例會將布爾值 true 和 false 轉換為不帶正負號的16位整數。

bool falseFlag = false;
bool trueFlag = true;

Console.WriteLine("{0} converts to {1}.", falseFlag,
                  Convert.ToInt16(falseFlag));
Console.WriteLine("{0} converts to {1}.", trueFlag,
                  Convert.ToUInt16(trueFlag));
// The example displays the following output:
//       False converts to 0.
//       True converts to 1.

let falseFlag = false
let trueFlag = true

printfn $"{falseFlag} converts to {Convert.ToInt16 falseFlag}."
printfn $"{trueFlag} converts to {Convert.ToInt16 trueFlag}."
// The example displays the following output:
//       False converts to 0.
//       True converts to 1.

Dim falseFlag As Boolean = False
Dim trueFlag As Boolean = True

Console.WriteLine("{0} converts to {1}.", falseFlag, _
                  Convert.ToUInt16(falseFlag))
Console.WriteLine("{0} converts to {1}.", trueFlag, _
                  Convert.ToUInt16(trueFlag))
' The example displays the following output:
'       False converts to 0.
'       True converts to 1.

適用於

ToUInt16(Object)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定之物件的值轉換為 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(System::Object ^ value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (object value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (object? value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : obj -> uint16

Public Shared Function ToUInt16 (value As Object) As UShort

參數

value: Object

實作 IConvertible 介面的物件，或是 null。

傳回

UInt16

與 value 相等的 16 位元不帶正負號的整數；如果 value 為 null，則為零。

屬性: CLSCompliantAttribute

例外狀況

FormatException

value 的格式不正確。

InvalidCastException

value 未實作 IConvertible 介面。

-或-

不支援轉換。

OverflowException

value 代表小於 UInt16.MinValue 或大於 UInt16.MaxValue 的數位。

範例

下列範例會嘗試將物件數位中的每個項目轉換成不帶正負號的16位整數。

object[] values= { true, -12, 163, 935, 'x', new DateTime(2009, 5, 12),
                   "104", "103.0", "-1", "1.00e2", "One", 1.00e2};
ushort result;

foreach (object value in values)
{
   try {
      result = Convert.ToUInt16(value);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        value.GetType().Name, value,
                        result.GetType().Name, result);
   }
   catch (OverflowException) {
      Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.",
                        value.GetType().Name, value);
   }
   catch (FormatException) {
      Console.WriteLine("The {0} value {1} is not in a recognizable format.",
                        value.GetType().Name, value);
   }
   catch (InvalidCastException) {
      Console.WriteLine("No conversion to a UInt16 exists for the {0} value {1}.",
                        value.GetType().Name, value);
   }
}
// The example displays the following output:
//    Converted the Boolean value 'True' to the UInt16 value 1.
//    The Int32 value -12 is outside the range of the UInt16 type.
//    Converted the Int32 value '163' to the UInt16 value 163.
//    Converted the Int32 value '935' to the UInt16 value 935.
//    Converted the Char value 'x' to the UInt16 value 120.
//    No conversion to a UInt16 exists for the DateTime value 5/12/2009 12:00:00 AM.
//    Converted the String value '104' to the UInt16 value 104.
//    The String value 103.0 is not in a recognizable format.
//    The String value -1 is outside the range of the UInt16 type.
//    The String value 1.00e2 is not in a recognizable format.
//    The String value One is not in a recognizable format.
//    Converted the Double value '100' to the UInt16 value 100.

let values: obj[] =
    [| true; -12; 163; 935; 'x'; DateTime(2009, 5, 12)
       "104"; "103.0"; "-1"; "1.00e2"; "One"; 1.00e2 |]

for value in values do
    try
        let result = Convert.ToUInt16 value
        printfn $"Converted the {value.GetType().Name} value '{value}' to the {result.GetType().Name} value {result}."
    with 
    | :? OverflowException ->
        printfn $"The {value.GetType().Name} value {value} is outside the range of the UInt16 type."
    | :? FormatException ->
        printfn $"The {value.GetType().Name} value {value} is not in a recognizable format."
    | :? InvalidCastException ->
        printfn $"No conversion to a UInt16 exists for the {value.GetType().Name} value {value}."
// The example displays the following output:
//    Converted the Boolean value 'True' to the UInt16 value 1.
//    The Int32 value -12 is outside the range of the UInt16 type.
//    Converted the Int32 value '163' to the UInt16 value 163.
//    Converted the Int32 value '935' to the UInt16 value 935.
//    Converted the Char value 'x' to the UInt16 value 120.
//    No conversion to a UInt16 exists for the DateTime value 5/12/2009 12:00:00 AM.
//    Converted the String value '104' to the UInt16 value 104.
//    The String value 103.0 is not in a recognizable format.
//    The String value -1 is outside the range of the UInt16 type.
//    The String value 1.00e2 is not in a recognizable format.
//    The String value One is not in a recognizable format.
//    Converted the Double value '100' to the UInt16 value 100.

   Dim values() As Object = { True, -12, 163, 935, "x"c, #5/12/2009#, _
                              "104", "103.0", "-1", _
                              "1.00e2", "One", 1.00e2}
   Dim result As UShort
   
   For Each value As Object In values
      Try
         result = Convert.ToUInt16(value)
         Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                           value.GetType().Name, value, _
                           result.GetType().Name, result)
      Catch e As OverflowException
         Console.WriteLine("The {0} value {1} is outside the range of the UInt16 type.", _
                           value.GetType().Name, value)
      Catch e As FormatException
         Console.WriteLine("The {0} value {1} is not in a recognizable format.", _
                           value.GetType().Name, value)
      Catch e As InvalidCastException
         Console.WriteLine("No conversion to an Int16 exists for the {0} value {1}.", _
                           value.GetType().Name, value)
                           
      End Try
   Next                           
   ' The example displays the following output:
'    Converted the Boolean value 'True' to the UInt16 value 1.
'    The Int32 value -12 is outside the range of the UInt16 type.
'    Converted the Int32 value '163' to the UInt16 value 163.
'    Converted the Int32 value '935' to the UInt16 value 935.
'    Converted the Char value 'x' to the UInt16 value 120.
'    No conversion to an Int16 exists for the DateTime value 5/12/2009 12:00:00 AM.
'    Converted the String value '104' to the UInt16 value 104.
'    The String value 103.0 is not in a recognizable format.
'    The String value -1 is outside the range of the UInt16 type.
'    The String value 1.00e2 is not in a recognizable format.
'    The String value One is not in a recognizable format.
'    Converted the Double value '100' to the UInt16 value 100.

備註

傳回值是叫 IConvertible.ToUInt16 用基礎型 value別之方法的結果。

適用於

ToUInt16(Double)

來源:: Convert.cs

來源:: Convert.cs

來源:: Convert.cs

重要

此 API 不符合 CLS 規範。

將指定之雙精確度浮點數的值，轉換為相等的 16 位元不帶正負號的整數。

public:
 static System::UInt16 ToUInt16(double value);

[System.CLSCompliant(false)]
public static ushort ToUInt16 (double value);

[<System.CLSCompliant(false)>]
static member ToUInt16 : double -> uint16

Public Shared Function ToUInt16 (value As Double) As UShort

參數

value: Double

要轉換的雙精確度浮點數。

傳回

UInt16

value，四捨五入為最接近的 16 位元不帶正負號整數。如果 value 介於兩個整數正中間時，則傳回偶數；也就是 4.5 會轉換為 4，5.5 會轉換為 6。

屬性: CLSCompliantAttribute

例外狀況

OverflowException

value 小於零或大於 UInt16.MaxValue。

範例

下列範例會將值陣列 Double 中的每個項目轉換成不帶正負號的16位整數。

double[] numbers = { Double.MinValue, -1.38e10, -1023.299, -12.98,
                    0, 9.113e-16, 103.919, 17834.191, Double.MaxValue };
ushort result;

foreach (double number in numbers)
{
   try {
      result = Convert.ToUInt16(number);
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.",
                        number.GetType().Name, number,
                        result.GetType().Name, result);
   }
   catch (OverflowException)
   {
      Console.WriteLine("{0} is outside the range of the UInt16 type.", number);
   }
}
// The example displays the following output:
//    -1.79769313486232E+308 is outside the range of the UInt16 type.
//    -13800000000 is outside the range of the UInt16 type.
//    -1023.299 is outside the range of the UInt16 type.
//    -12.98 is outside the range of the UInt16 type.
//    Converted the Double value '0' to the UInt16 value 0.
//    Converted the Double value '9.113E-16' to the UInt16 value 0.
//    Converted the Double value '103.919' to the UInt16 value 104.
//    Converted the Double value '17834.191' to the UInt16 value 17834.
//    1.79769313486232E+308 is outside the range of the UInt16 type.

let numbers = 
    [| Double.MinValue; -1.38e10; -1023.299; -12.98
       0; 9.113e-16; 103.919; 17834.191; Double.MaxValue |]

for number in numbers do
    try
        let result = Convert.ToUInt16 number
        printfn $"Converted the {number.GetType().Name} value '{number}' to the {result.GetType().Name} value {result}."
    with :? OverflowException ->
        printfn $"{number} is outside the range of the UInt16 type."
// The example displays the following output:
//    -1.79769313486232E+308 is outside the range of the UInt16 type.
//    -13800000000 is outside the range of the UInt16 type.
//    -1023.299 is outside the range of the UInt16 type.
//    -12.98 is outside the range of the UInt16 type.
//    Converted the Double value '0' to the UInt16 value 0.
//    Converted the Double value '9.113E-16' to the UInt16 value 0.
//    Converted the Double value '103.919' to the UInt16 value 104.
//    Converted the Double value '17834.191' to the UInt16 value 17834.
//    1.79769313486232E+308 is outside the range of the UInt16 type.

Dim values() As Double = { Double.MinValue, -1.38e10, -1023.299, -12.98, _
                           0, 9.113e-16, 103.919, 17834.191, Double.MaxValue }
Dim result As UShort

For Each value As Double In values
   Try
      result = Convert.ToUInt16(value)
      Console.WriteLine("Converted the {0} value '{1}' to the {2} value {3}.", _
                        value.GetType().Name, value, _
                        result.GetType().Name, result)
   Catch e As OverflowException
      Console.WriteLine("{0} is outside the range of the UInt16 type.", value)
   End Try   
Next                                 
' The example displays the following output:
'    -1.79769313486232E+308 is outside the range of the UInt16 type.
'    -13800000000 is outside the range of the UInt16 type.
'    -1023.299 is outside the range of the UInt16 type.
'    -12.98 is outside the range of the UInt16 type.
'    Converted the Double value '0' to the UInt16 value 0.
'    Converted the Double value '9.113E-16' to the UInt16 value 0.
'    Converted the Double value '103.919' to the UInt16 value 104.
'    Converted the Double value '17834.191' to the UInt16 value 17834.
'    1.79769313486232E+308 is outside the range of the UInt16 type.

另請參閱

Double
Round

適用於