Encoding.GetBytes 方法
定義
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。
在衍生類別中覆寫時,將一組字元編碼成位元組序列。
多載
GetBytes(Char[]) |
在衍生類別中覆寫時,將指定字元陣列中的所有字元編碼成位元組序列。 |
GetBytes(String) |
在衍生類別中覆寫時,將指定字串中的所有字元編碼成位元組序列。 |
GetBytes(ReadOnlySpan<Char>, Span<Byte>) |
在衍生類別中覆寫時,從指定的唯讀範圍將一組字元編碼到位元組範圍。 |
GetBytes(Char[], Int32, Int32) |
在衍生類別中覆寫時,將指定字元陣列中的一組字元編碼成位元組序列。 |
GetBytes(String, Int32, Int32) |
在衍生類別中覆寫時,從指定字串中指定的 |
GetBytes(Char*, Int32, Byte*, Int32) |
在衍生類別中覆寫時,從指定字元指標開始將一組字元編碼成位元組序列 (會從指定的位元組指標開始存放這些位元組)。 |
GetBytes(Char[], Int32, Int32, Byte[], Int32) |
在衍生類別中覆寫時,將指定字元陣列中的一組字元編碼成指定的位元組陣列。 |
GetBytes(String, Int32, Int32, Byte[], Int32) |
在衍生類別中覆寫時,將指定字串中的一組字元編碼成指定的位元組陣列。 |
GetBytes(Char[])
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,將指定字元陣列中的所有字元編碼成位元組序列。
public:
virtual cli::array <System::Byte> ^ GetBytes(cli::array <char> ^ chars);
public virtual byte[] GetBytes (char[] chars);
abstract member GetBytes : char[] -> byte[]
override this.GetBytes : char[] -> byte[]
Public Overridable Function GetBytes (chars As Char()) As Byte()
參數
- chars
- Char[]
字元陣列,包含要編碼的字元。
傳回
位元組陣列,包含將指定之一組字元編碼之後的結果。
例外狀況
chars
為 null
。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
範例
下列範例會決定編碼字元數位所需的位元組數目、編碼字元,並顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
array<Char>^myChars = gcnew array<Char>{
L'z','a',L'\u0306',L'\u01FD',L'\u03B2',L'\xD8FF',L'\xDCFF'
};
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, u7 );
PrintCountsAndBytes( myChars, u8 );
PrintCountsAndBytes( myChars, u16LE );
PrintCountsAndBytes( myChars, u16BE );
PrintCountsAndBytes( myChars, u32 );
}
void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( chars );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( chars->Length );
Console::Write( " {0,-3} :", iMBC );
// Encode the array of chars.
array<Byte>^bytes = enc->GetBytes( chars );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
char[] myChars = new char[] { 'z', 'a', '\u0306', '\u01FD', '\u03B2', '\uD8FF', '\uDCFF' };
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, u7 );
PrintCountsAndBytes( myChars, u8 );
PrintCountsAndBytes( myChars, u16LE );
PrintCountsAndBytes( myChars, u16BE );
PrintCountsAndBytes( myChars, u32 );
}
public static void PrintCountsAndBytes( char[] chars, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( chars );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( chars.Length );
Console.Write( " {0,-3} :", iMBC );
// Encode the array of chars.
byte[] bytes = enc.GetBytes( chars );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF)}
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode the entire array, and print out the counts and the resulting bytes.
PrintCountsAndBytes(myChars, u7)
PrintCountsAndBytes(myChars, u8)
PrintCountsAndBytes(myChars, u16LE)
PrintCountsAndBytes(myChars, u16BE)
PrintCountsAndBytes(myChars, u32)
End Sub
Public Shared Sub PrintCountsAndBytes(chars() As Char, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(chars)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(chars.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the array of chars.
Dim bytes As Byte() = enc.GetBytes(chars)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
'System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
備註
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該呼叫 方法的 GetBytes 字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過請記住,此方法版本有時不安全,因為需要指標。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
另請參閱
適用於
GetBytes(String)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,將指定字串中的所有字元編碼成位元組序列。
public:
virtual cli::array <System::Byte> ^ GetBytes(System::String ^ s);
public virtual byte[] GetBytes (string s);
abstract member GetBytes : string -> byte[]
override this.GetBytes : string -> byte[]
Public Overridable Function GetBytes (s As String) As Byte()
參數
- s
- String
字串,包含要編碼的字元。
傳回
位元組陣列,包含將指定之一組字元編碼之後的結果。
例外狀況
s
為 null
。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
範例
下列範例會決定編碼字串或字串範圍所需的位元組數目、編碼字元,並顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( String^ s, Encoding^ enc );
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String^ myStr = L"za\u0306\u01FD\u03B2\xD8FF\xDCFF";
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console::WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
void PrintCountsAndBytes( String^ s, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( s->Length );
Console::Write( " {0,-3} :", iMBC );
// Encode the entire string.
array<Byte>^bytes = enc->GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s->ToCharArray(), index, count );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( count );
Console::Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
array<Byte>^bytes = gcnew array<Byte>(iBC);
enc->GetBytes( s, index, count, bytes, bytes->GetLowerBound( 0 ) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String myStr = "za\u0306\u01FD\u03B2\uD8FF\uDCFF";
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console.WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
public static void PrintCountsAndBytes( String s, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( s.Length );
Console.Write( " {0,-3} :", iMBC );
// Encode the entire string.
byte[] bytes = enc.GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintCountsAndBytes( String s, int index, int count, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s.ToCharArray(), index, count );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( count );
Console.Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
byte[] bytes = new byte[iBC];
enc.GetBytes( s, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2) & ChrW(&HD8FF) & ChrW(&HDCFF)
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the entire string:")
PrintCountsAndBytes(myStr, u7)
PrintCountsAndBytes(myStr, u8)
PrintCountsAndBytes(myStr, u16LE)
PrintCountsAndBytes(myStr, u16BE)
PrintCountsAndBytes(myStr, u32)
Console.WriteLine()
' Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the characters from index 4 through 6:")
PrintCountsAndBytes(myStr, 4, 3, u7)
PrintCountsAndBytes(myStr, 4, 3, u8)
PrintCountsAndBytes(myStr, 4, 3, u16LE)
PrintCountsAndBytes(myStr, 4, 3, u16BE)
PrintCountsAndBytes(myStr, 4, 3, u32)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(s.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the entire string.
Dim bytes As Byte() = enc.GetBytes(s)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, index As Integer, count As Integer, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s.ToCharArray(), index, count)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(count)
Console.Write(" {0,-3} :", iMBC)
' Encode a range of characters in the string.
' NOTE: In VB.NET, arrays contain one extra element by default.
' The following line creates the array with the exact number of elements required.
Dim bytes(iBC - 1) As Byte
enc.GetBytes(s, index, count, bytes, bytes.GetLowerBound(0))
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'Encoding the entire string:
'System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
'System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
'
'Encoding the characters from index 4 through 6:
'System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
'System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
備註
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過請記住,此方法版本有時不安全,因為需要指標。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
另請參閱
適用於
GetBytes(ReadOnlySpan<Char>, Span<Byte>)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,從指定的唯讀範圍將一組字元編碼到位元組範圍。
public:
virtual int GetBytes(ReadOnlySpan<char> chars, Span<System::Byte> bytes);
public virtual int GetBytes (ReadOnlySpan<char> chars, Span<byte> bytes);
abstract member GetBytes : ReadOnlySpan<char> * Span<byte> -> int
override this.GetBytes : ReadOnlySpan<char> * Span<byte> -> int
Public Overridable Function GetBytes (chars As ReadOnlySpan(Of Char), bytes As Span(Of Byte)) As Integer
參數
- chars
- ReadOnlySpan<Char>
範圍,其包含一組要編碼的字元。
傳回
已編碼的位元組數。
備註
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
適用於
GetBytes(Char[], Int32, Int32)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,將指定字元陣列中的一組字元編碼成位元組序列。
public:
virtual cli::array <System::Byte> ^ GetBytes(cli::array <char> ^ chars, int index, int count);
public virtual byte[] GetBytes (char[] chars, int index, int count);
abstract member GetBytes : char[] * int * int -> byte[]
override this.GetBytes : char[] * int * int -> byte[]
Public Overridable Function GetBytes (chars As Char(), index As Integer, count As Integer) As Byte()
參數
- chars
- Char[]
包含要解碼之一組字元的字元陣列。
- index
- Int32
要編碼的第一個字元索引。
- count
- Int32
要編碼的字元數。
傳回
位元組陣列,包含將指定之一組字元編碼之後的結果。
例外狀況
chars
為 null
。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
範例
下列範例會決定從字元數位列編碼三個字元所需的位元組數目、編碼字元,並顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( array<Char>^chars, int index, int count, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
array<Char>^myChars = gcnew array<Char>{
L'z',L'a',L'\u0306',L'\u01FD',L'\u03B2',L'\xD8FF',L'\xDCFF'
};
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, 4, 3, u7 );
PrintCountsAndBytes( myChars, 4, 3, u8 );
PrintCountsAndBytes( myChars, 4, 3, u16LE );
PrintCountsAndBytes( myChars, 4, 3, u16BE );
PrintCountsAndBytes( myChars, 4, 3, u32 );
}
void PrintCountsAndBytes( array<Char>^chars, int index, int count, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( chars, index, count );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( count );
Console::Write( " {0,-3} :", iMBC );
// Encode the array of chars.
array<Byte>^bytes = enc->GetBytes( chars, index, count );
// The following is an alternative way to encode the array of chars:
// byte[] bytes = new byte[iBC];
// enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
char[] myChars = new char[] { 'z', 'a', '\u0306', '\u01FD', '\u03B2', '\uD8FF', '\uDCFF' };
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, 4, 3, u7 );
PrintCountsAndBytes( myChars, 4, 3, u8 );
PrintCountsAndBytes( myChars, 4, 3, u16LE );
PrintCountsAndBytes( myChars, 4, 3, u16BE );
PrintCountsAndBytes( myChars, 4, 3, u32 );
}
public static void PrintCountsAndBytes( char[] chars, int index, int count, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( chars, index, count );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( count );
Console.Write( " {0,-3} :", iMBC );
// Encode the array of chars.
byte[] bytes = enc.GetBytes( chars, index, count );
// The following is an alternative way to encode the array of chars:
// byte[] bytes = new byte[iBC];
// enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF) }
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes(myChars, 4, 3, u7)
PrintCountsAndBytes(myChars, 4, 3, u8)
PrintCountsAndBytes(myChars, 4, 3, u16LE)
PrintCountsAndBytes(myChars, 4, 3, u16BE)
PrintCountsAndBytes(myChars, 4, 3, u32)
End Sub
Public Shared Sub PrintCountsAndBytes(chars() As Char, index As Integer, count As Integer, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(chars, index, count)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(count)
Console.Write(" {0,-3} :", iMBC)
' Encode the array of chars.
Dim bytes As Byte() = enc.GetBytes(chars, index, count)
' The following is an alternative way to encode the array of chars:
' NOTE: In VB.NET, arrays contain one extra element by default.
' The following line creates the array with the exact number of elements required.
' Dim bytes(iBC - 1) As Byte
' enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) )
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
'System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
備註
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過請記住,此方法版本有時不安全,因為需要指標。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
另請參閱
適用於
GetBytes(String, Int32, Int32)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,從指定字串中指定的 index
開始,將 count
指定的字元數編碼到位元組陣列。
public:
cli::array <System::Byte> ^ GetBytes(System::String ^ s, int index, int count);
public byte[] GetBytes (string s, int index, int count);
member this.GetBytes : string * int * int -> byte[]
Public Function GetBytes (s As String, index As Integer, count As Integer) As Byte()
參數
- s
- String
字串,包含要編碼的字元。
- index
- Int32
字串內的索引,要開始編碼的位置。
- count
- Int32
要編碼的字元數。
傳回
位元組陣列,包含將指定之一組字元編碼之後的結果。
範例
下列範例會決定編碼字串或字串範圍所需的位元組數目、編碼字元,並顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( String^ s, Encoding^ enc );
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String^ myStr = L"za\u0306\u01FD\u03B2\xD8FF\xDCFF";
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console::WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
void PrintCountsAndBytes( String^ s, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( s->Length );
Console::Write( " {0,-3} :", iMBC );
// Encode the entire string.
array<Byte>^bytes = enc->GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s->ToCharArray(), index, count );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( count );
Console::Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
array<Byte>^bytes = gcnew array<Byte>(iBC);
enc->GetBytes( s, index, count, bytes, bytes->GetLowerBound( 0 ) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String myStr = "za\u0306\u01FD\u03B2\uD8FF\uDCFF";
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console.WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
public static void PrintCountsAndBytes( String s, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( s.Length );
Console.Write( " {0,-3} :", iMBC );
// Encode the entire string.
byte[] bytes = enc.GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintCountsAndBytes( String s, int index, int count, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s.ToCharArray(), index, count );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( count );
Console.Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
byte[] bytes = new byte[iBC];
enc.GetBytes( s, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2) & ChrW(&HD8FF) & ChrW(&HDCFF)
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the entire string:")
PrintCountsAndBytes(myStr, u7)
PrintCountsAndBytes(myStr, u8)
PrintCountsAndBytes(myStr, u16LE)
PrintCountsAndBytes(myStr, u16BE)
PrintCountsAndBytes(myStr, u32)
Console.WriteLine()
' Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the characters from index 4 through 6:")
PrintCountsAndBytes(myStr, 4, 3, u7)
PrintCountsAndBytes(myStr, 4, 3, u8)
PrintCountsAndBytes(myStr, 4, 3, u16LE)
PrintCountsAndBytes(myStr, 4, 3, u16BE)
PrintCountsAndBytes(myStr, 4, 3, u32)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(s.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the entire string.
Dim bytes As Byte() = enc.GetBytes(s)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, index As Integer, count As Integer, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s.ToCharArray(), index, count)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(count)
Console.Write(" {0,-3} :", iMBC)
' Encode a range of characters in the string.
' NOTE: In VB.NET, arrays contain one extra element by default.
' The following line creates the array with the exact number of elements required.
Dim bytes(iBC - 1) As Byte
enc.GetBytes(s, index, count, bytes, bytes.GetLowerBound(0))
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'Encoding the entire string:
'System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
'System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
'
'Encoding the characters from index 4 through 6:
'System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
'System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
備註
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過請記住,此方法版本有時不安全,因為需要指標。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
適用於
GetBytes(Char*, Int32, Byte*, Int32)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
重要
此 API 不符合 CLS 規範。
在衍生類別中覆寫時,從指定字元指標開始將一組字元編碼成位元組序列 (會從指定的位元組指標開始存放這些位元組)。
public:
virtual int GetBytes(char* chars, int charCount, System::Byte* bytes, int byteCount);
[System.CLSCompliant(false)]
[System.Security.SecurityCritical]
public virtual int GetBytes (char* chars, int charCount, byte* bytes, int byteCount);
[System.CLSCompliant(false)]
public virtual int GetBytes (char* chars, int charCount, byte* bytes, int byteCount);
[System.CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
public virtual int GetBytes (char* chars, int charCount, byte* bytes, int byteCount);
[System.CLSCompliant(false)]
[System.Security.SecurityCritical]
[System.Runtime.InteropServices.ComVisible(false)]
public virtual int GetBytes (char* chars, int charCount, byte* bytes, int byteCount);
[<System.CLSCompliant(false)>]
[<System.Security.SecurityCritical>]
abstract member GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
override this.GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
[<System.CLSCompliant(false)>]
abstract member GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
override this.GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
[<System.CLSCompliant(false)>]
[<System.Runtime.InteropServices.ComVisible(false)>]
abstract member GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
override this.GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
[<System.CLSCompliant(false)>]
[<System.Security.SecurityCritical>]
[<System.Runtime.InteropServices.ComVisible(false)>]
abstract member GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
override this.GetBytes : nativeptr<char> * int * nativeptr<byte> * int -> int
參數
- chars
- Char*
要編碼的第一個字元指標。
- charCount
- Int32
要編碼的字元數。
- bytes
- Byte*
開始寫入結果位元組序列的位置指標。
- byteCount
- Int32
寫入的最大位元組數。
傳回
bytes
參數所指示位置上寫入的實際位元組數目。
- 屬性
例外狀況
charCount
或 byteCount
小於零。
byteCount
小於結果位元組數。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
備註
若要計算儲存所產生位元組所需的確切數組大小 GetBytes ,請呼叫 GetByteCount 方法。 若要計算數位大小上限,請呼叫 GetMaxByteCount 方法。 方法 GetByteCount 通常允許配置較少的記憶體,而 GetMaxByteCount 方法通常會執行得更快。
如果要轉換的數據僅在順序塊中可用(例如從流中讀取的數據),或者如果數據量太大以至於需要將其分成較小的塊,則應使用提供的Decoder或Encoder對象 分別由GetDecoder或GetEncoder種方法派生的類。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要維護呼叫之間的狀態,並考慮正在使用的物件 Encoder 所保存的狀態。 (例如,包含 Surrogate 字組的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過請記住,此方法版本有時不安全,因為需要指標。
如果您的 app 必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法, GetByteCount而不是 。 轉換方法會儘可能轉換數據,並在輸出緩衝區太小時擲回例外狀況。 針對數據流的連續編碼,此方法通常是最佳選擇。
另請參閱
適用於
GetBytes(Char[], Int32, Int32, Byte[], Int32)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,將指定字元陣列中的一組字元編碼成指定的位元組陣列。
public:
abstract int GetBytes(cli::array <char> ^ chars, int charIndex, int charCount, cli::array <System::Byte> ^ bytes, int byteIndex);
public abstract int GetBytes (char[] chars, int charIndex, int charCount, byte[] bytes, int byteIndex);
abstract member GetBytes : char[] * int * int * byte[] * int -> int
Public MustOverride Function GetBytes (chars As Char(), charIndex As Integer, charCount As Integer, bytes As Byte(), byteIndex As Integer) As Integer
參數
- chars
- Char[]
包含要解碼之一組字元的字元陣列。
- charIndex
- Int32
要編碼的第一個字元索引。
- charCount
- Int32
要編碼的字元數。
- bytes
- Byte[]
要包含結果位元組序列的位元組陣列。
- byteIndex
- Int32
要開始寫入結果位元組序列的索引。
傳回
寫入 bytes
的實際位元組數。
例外狀況
charIndex
、charCount
或 byteIndex
小於零。
-或-
charIndex
與 charCount
不代表 chars
中有效的範圍。
-或-
byteIndex
在 bytes
中不是有效的索引。
從 bytes
到陣列結尾處,byteIndex
沒有足夠的容量容納結果位元組。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
範例
下列範例會決定從字元數位列編碼三個字元所需的位元組數目、編碼字元,並顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( array<Char>^chars, int index, int count, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
array<Char>^myChars = gcnew array<Char>{
L'z',L'a',L'\u0306',L'\u01FD',L'\u03B2',L'\xD8FF',L'\xDCFF'
};
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, 4, 3, u7 );
PrintCountsAndBytes( myChars, 4, 3, u8 );
PrintCountsAndBytes( myChars, 4, 3, u16LE );
PrintCountsAndBytes( myChars, 4, 3, u16BE );
PrintCountsAndBytes( myChars, 4, 3, u32 );
}
void PrintCountsAndBytes( array<Char>^chars, int index, int count, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( chars, index, count );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( count );
Console::Write( " {0,-3} :", iMBC );
// Encode the array of chars.
array<Byte>^bytes = enc->GetBytes( chars, index, count );
// The following is an alternative way to encode the array of chars:
// byte[] bytes = new byte[iBC];
// enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
char[] myChars = new char[] { 'z', 'a', '\u0306', '\u01FD', '\u03B2', '\uD8FF', '\uDCFF' };
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes( myChars, 4, 3, u7 );
PrintCountsAndBytes( myChars, 4, 3, u8 );
PrintCountsAndBytes( myChars, 4, 3, u16LE );
PrintCountsAndBytes( myChars, 4, 3, u16BE );
PrintCountsAndBytes( myChars, 4, 3, u32 );
}
public static void PrintCountsAndBytes( char[] chars, int index, int count, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( chars, index, count );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( count );
Console.Write( " {0,-3} :", iMBC );
// Encode the array of chars.
byte[] bytes = enc.GetBytes( chars, index, count );
// The following is an alternative way to encode the array of chars:
// byte[] bytes = new byte[iBC];
// enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF) }
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode three characters starting at index 4, and print out the counts and the resulting bytes.
PrintCountsAndBytes(myChars, 4, 3, u7)
PrintCountsAndBytes(myChars, 4, 3, u8)
PrintCountsAndBytes(myChars, 4, 3, u16LE)
PrintCountsAndBytes(myChars, 4, 3, u16BE)
PrintCountsAndBytes(myChars, 4, 3, u32)
End Sub
Public Shared Sub PrintCountsAndBytes(chars() As Char, index As Integer, count As Integer, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(chars, index, count)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(count)
Console.Write(" {0,-3} :", iMBC)
' Encode the array of chars.
Dim bytes As Byte() = enc.GetBytes(chars, index, count)
' The following is an alternative way to encode the array of chars:
' NOTE: In VB.NET, arrays contain one extra element by default.
' The following line creates the array with the exact number of elements required.
' Dim bytes(iBC - 1) As Byte
' enc.GetBytes( chars, index, count, bytes, bytes.GetLowerBound(0) )
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
'System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
備註
若要計算儲存所產生位元組所需的 GetBytes 確切數位大小,您應該呼叫 GetByteCount 方法。 若要計算數位大小上限,請呼叫 GetMaxByteCount 方法。 方法 GetByteCount 通常允許配置較少的記憶體,而 GetMaxByteCount 方法通常會執行得更快。
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定一組 Unicode 字元編碼所產生的位元組數目,而 GetBytes 方法會執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,相較於 Encoder.GetBytes 方法,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要在呼叫之間維護狀態,並考慮所使用物件所保存 Encoder 的狀態。 例如, (包含 Surrogate 配對的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過,請記住,此方法版本有時不安全,因為需要指標。
如果您的應用程式必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法,而不是 GetByteCount。 轉換方法會盡可能轉換數據,而且如果輸出緩衝區太小,則會擲回例外狀況。 對於數據流的連續編碼,此方法通常是最佳選擇。
另請參閱
適用於
GetBytes(String, Int32, Int32, Byte[], Int32)
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
- 來源:
- Encoding.cs
在衍生類別中覆寫時,將指定字串中的一組字元編碼成指定的位元組陣列。
public:
virtual int GetBytes(System::String ^ s, int charIndex, int charCount, cli::array <System::Byte> ^ bytes, int byteIndex);
public virtual int GetBytes (string s, int charIndex, int charCount, byte[] bytes, int byteIndex);
abstract member GetBytes : string * int * int * byte[] * int -> int
override this.GetBytes : string * int * int * byte[] * int -> int
Public Overridable Function GetBytes (s As String, charIndex As Integer, charCount As Integer, bytes As Byte(), byteIndex As Integer) As Integer
參數
- s
- String
字串,包含要編碼的一組字元。
- charIndex
- Int32
要編碼的第一個字元索引。
- charCount
- Int32
要編碼的字元數。
- bytes
- Byte[]
要包含結果位元組序列的位元組陣列。
- byteIndex
- Int32
要開始寫入結果位元組序列的索引。
傳回
寫入 bytes
的實際位元組數。
例外狀況
charIndex
、charCount
或 byteIndex
小於零。
-或-
charIndex
與 charCount
不代表 chars
中有效的範圍。
-或-
byteIndex
在 bytes
中不是有效的索引。
從 bytes
到陣列結尾處,byteIndex
沒有足夠的容量容納結果位元組。
發生後援 (如需詳細資訊,請參閱 .NET 中的字元編碼)
-和-
範例
下列範例會決定編碼字串或字串範圍所需的位元組數目、編碼字元,以及顯示產生的位元組。
using namespace System;
using namespace System::Text;
void PrintCountsAndBytes( String^ s, Encoding^ enc );
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int main()
{
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String^ myStr = L"za\u0306\u01FD\u03B2\xD8FF\xDCFF";
// Get different encodings.
Encoding^ u7 = Encoding::UTF7;
Encoding^ u8 = Encoding::UTF8;
Encoding^ u16LE = Encoding::Unicode;
Encoding^ u16BE = Encoding::BigEndianUnicode;
Encoding^ u32 = Encoding::UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console::WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console::WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
void PrintCountsAndBytes( String^ s, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( s->Length );
Console::Write( " {0,-3} :", iMBC );
// Encode the entire string.
array<Byte>^bytes = enc->GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintCountsAndBytes( String^ s, int index, int count, Encoding^ enc )
{
// Display the name of the encoding used.
Console::Write( "{0,-30} :", enc );
// Display the exact byte count.
int iBC = enc->GetByteCount( s->ToCharArray(), index, count );
Console::Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc->GetMaxByteCount( count );
Console::Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
array<Byte>^bytes = gcnew array<Byte>(iBC);
enc->GetBytes( s, index, count, bytes, bytes->GetLowerBound( 0 ) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
void PrintHexBytes( array<Byte>^bytes )
{
if ( (bytes == nullptr) || (bytes->Length == 0) )
Console::WriteLine( "<none>" );
else
{
for ( int i = 0; i < bytes->Length; i++ )
Console::Write( "{0:X2} ", bytes[ i ] );
Console::WriteLine();
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
using System;
using System.Text;
public class SamplesEncoding {
public static void Main() {
// The characters to encode:
// Latin Small Letter Z (U+007A)
// Latin Small Letter A (U+0061)
// Combining Breve (U+0306)
// Latin Small Letter AE With Acute (U+01FD)
// Greek Small Letter Beta (U+03B2)
// a high-surrogate value (U+D8FF)
// a low-surrogate value (U+DCFF)
String myStr = "za\u0306\u01FD\u03B2\uD8FF\uDCFF";
// Get different encodings.
Encoding u7 = Encoding.UTF7;
Encoding u8 = Encoding.UTF8;
Encoding u16LE = Encoding.Unicode;
Encoding u16BE = Encoding.BigEndianUnicode;
Encoding u32 = Encoding.UTF32;
// Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the entire string:" );
PrintCountsAndBytes( myStr, u7 );
PrintCountsAndBytes( myStr, u8 );
PrintCountsAndBytes( myStr, u16LE );
PrintCountsAndBytes( myStr, u16BE );
PrintCountsAndBytes( myStr, u32 );
Console.WriteLine();
// Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine( "Encoding the characters from index 4 through 6:" );
PrintCountsAndBytes( myStr, 4, 3, u7 );
PrintCountsAndBytes( myStr, 4, 3, u8 );
PrintCountsAndBytes( myStr, 4, 3, u16LE );
PrintCountsAndBytes( myStr, 4, 3, u16BE );
PrintCountsAndBytes( myStr, 4, 3, u32 );
}
public static void PrintCountsAndBytes( String s, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( s.Length );
Console.Write( " {0,-3} :", iMBC );
// Encode the entire string.
byte[] bytes = enc.GetBytes( s );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintCountsAndBytes( String s, int index, int count, Encoding enc ) {
// Display the name of the encoding used.
Console.Write( "{0,-30} :", enc.ToString() );
// Display the exact byte count.
int iBC = enc.GetByteCount( s.ToCharArray(), index, count );
Console.Write( " {0,-3}", iBC );
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount( count );
Console.Write( " {0,-3} :", iMBC );
// Encode a range of characters in the string.
byte[] bytes = new byte[iBC];
enc.GetBytes( s, index, count, bytes, bytes.GetLowerBound(0) );
// Display all the encoded bytes.
PrintHexBytes( bytes );
}
public static void PrintHexBytes( byte[] bytes ) {
if (( bytes == null ) || ( bytes.Length == 0 ))
{
Console.WriteLine( "<none>" );
}
else {
for ( int i = 0; i < bytes.Length; i++ )
Console.Write( "{0:X2} ", bytes[i] );
Console.WriteLine();
}
}
}
/*
This code produces the following output.
Encoding the entire string:
System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
Encoding the characters from index 4 through 6:
System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub Main()
' The characters to encode:
' Latin Small Letter Z (U+007A)
' Latin Small Letter A (U+0061)
' Combining Breve (U+0306)
' Latin Small Letter AE With Acute (U+01FD)
' Greek Small Letter Beta (U+03B2)
' a high-surrogate value (U+D8FF)
' a low-surrogate value (U+DCFF)
Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2) & ChrW(&HD8FF) & ChrW(&HDCFF)
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = Encoding.UTF32
' Encode the entire string, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the entire string:")
PrintCountsAndBytes(myStr, u7)
PrintCountsAndBytes(myStr, u8)
PrintCountsAndBytes(myStr, u16LE)
PrintCountsAndBytes(myStr, u16BE)
PrintCountsAndBytes(myStr, u32)
Console.WriteLine()
' Encode three characters starting at index 4, and print out the counts and the resulting bytes.
Console.WriteLine("Encoding the characters from index 4 through 6:")
PrintCountsAndBytes(myStr, 4, 3, u7)
PrintCountsAndBytes(myStr, 4, 3, u8)
PrintCountsAndBytes(myStr, 4, 3, u16LE)
PrintCountsAndBytes(myStr, 4, 3, u16BE)
PrintCountsAndBytes(myStr, 4, 3, u32)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(s.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the entire string.
Dim bytes As Byte() = enc.GetBytes(s)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Overloads Public Shared Sub PrintCountsAndBytes(s As String, index As Integer, count As Integer, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(s.ToCharArray(), index, count)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(count)
Console.Write(" {0,-3} :", iMBC)
' Encode a range of characters in the string.
' NOTE: In VB.NET, arrays contain one extra element by default.
' The following line creates the array with the exact number of elements required.
Dim bytes(iBC - 1) As Byte
enc.GetBytes(s, index, count, bytes, bytes.GetLowerBound(0))
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'This code produces the following output.
'
'Encoding the entire string:
'System.Text.UTF7Encoding : 18 23 :7A 61 2B 41 77 59 42 2F 51 4F 79 32 50 2F 63 2F 77 2D
'System.Text.UTF8Encoding : 12 24 :7A 61 CC 86 C7 BD CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 14 16 :7A 00 61 00 06 03 FD 01 B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 14 16 :00 7A 00 61 03 06 01 FD 03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 24 32 :7A 00 00 00 61 00 00 00 06 03 00 00 FD 01 00 00 B2 03 00 00 FF FC 04 00
'
'Encoding the characters from index 4 through 6:
'System.Text.UTF7Encoding : 10 11 :2B 41 37 4C 59 2F 39 7A 2F 2D
'System.Text.UTF8Encoding : 6 12 :CE B2 F1 8F B3 BF
'System.Text.UnicodeEncoding : 6 8 :B2 03 FF D8 FF DC
'System.Text.UnicodeEncoding : 6 8 :03 B2 D8 FF DC FF
'System.Text.UTF32Encoding : 8 16 :B2 03 00 00 FF FC 04 00
備註
若要計算儲存結果位元組所需的 GetBytes 確切數位大小,您應該呼叫 GetByteCount 方法。 若要計算數位大小上限,請呼叫 GetMaxByteCount 方法。 方法 GetByteCount 通常允許配置較少的記憶體,而 GetMaxByteCount 方法通常執行速度較快。
如果要轉換的數據只能在循序區塊中使用, (例如從數據流讀取的數據) ,或如果數據量太大而需要分割成較小的區塊,則您應該分別使用 DecoderEncoder 方法或 方法所提供的 GetDecoder 或 GetEncoder 方法。
方法 GetByteCount 會決定編碼一組 Unicode 字元所產生的位元組數目,而方法會 GetBytes 執行實際的編碼。 方法 Encoding.GetBytes 預期會進行離散轉換,與方法相反 Encoder.GetBytes ,此方法會處理單一輸入數據流上的多個轉換。
支持數個和 GetByteCountGetBytes 版本。 以下是使用這些方法的一些程式設計考慮:
您的應用程式可能需要將許多輸入字元編碼為代碼頁,並使用多個呼叫來處理字元。 在此情況下,您可能需要在呼叫之間維護狀態,並考慮所使用物件所保存 Encoder 的狀態。 例如, (包含 Surrogate 配對的字元序列可能會以高 Surrogate 結尾。 Encoder 會記住高 Surrogate,使其可以在下列呼叫 Encoding 開始時與低 Surrogate 結合。將無法維護狀態,因此字元會傳送至 EncoderFallback.)
如果您的應用程式處理字串輸入,您應該使用 的 GetBytes字串版本。
的 Unicode 字元緩衝區版本 GetBytes(Char*, Int32, Byte*, Int32) 允許一些快速的技術,特別是使用 Encoder 物件或插入現有緩衝區的多個呼叫。 不過,請記住,此方法版本有時不安全,因為需要指標。
如果您的應用程式必須轉換大量數據,它應該重複使用輸出緩衝區。 在此情況下, GetBytes 支援位元組陣組的版本是最佳選擇。
請考慮使用 Encoder.Convert 方法,而不是 GetByteCount。 轉換方法會盡可能轉換數據,而且如果輸出緩衝區太小,則會擲回例外狀況。 對於數據流的連續編碼,此方法通常是最佳選擇。