Encoding.Unicode 屬性
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。
會用小端序編碼 UTF-16 格式。
public:
static property System::Text::Encoding ^ Unicode { System::Text::Encoding ^ get(); };public static System.Text.Encoding Unicode { get; }static member Unicode : System.Text.EncodingPublic Shared ReadOnly Property Unicode As Encoding屬性值
一種使用 little endian byte order 的 UTF-16 格式編碼。
範例
以下範例決定編碼字元陣列所需的位元組數，編碼字元，並顯示產生的位元組。
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
關於 .NET 支援的編碼資訊及使用哪種 Unicode 編碼的討論，請參見 .NET<> 中的
UnicodeEncoding這個屬性回傳的物件可能沒有適合你的應用程式的行為。 它使用替換備援來替換每個無法編碼的字串，以及每個無法解碼的位元組，並用問號（“？”）字元替換。 相反地，你可以呼叫建 UnicodeEncoding.UnicodeEncoding(Boolean, Boolean, Boolean) 構子來實例一個小型端序 UnicodeEncoding 物件，其備註是 a EncoderFallbackException 或 DecoderFallbackException，如下範例所示。
using System;
using System.Text;
public class Example
{
public static void Main()
{
byte[] bytes = { 0x20, 0x00, 0x01, 0xD8, 0x68, 0x00, 0xA7, 0x00 };
Encoding enc = new UnicodeEncoding(false, true, true);
try {
string value = enc.GetString(bytes);
Console.WriteLine();
Console.WriteLine("'{0}'", value);
}
catch (DecoderFallbackException e) {
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index);
}
}
private static string ShowBytes(byte[] bytes)
{
string returnString = null;
foreach (var byteValue in bytes)
returnString += String.Format("0x{0:X2} ", byteValue);
return returnString.Trim();
}
}
// The example displays the following output:
// Unable to decode 0x01 0xD8 at index 4
Imports System.Text
Module Example
Public Sub Main()
Dim bytes() As Byte = { &h20, &h00, &h01, &hD8, &h68, &h00, &hA7, &h00}
Dim enc As Encoding = New UnicodeEncoding(False, True, True)
Try
Dim value As String = enc.GetString(bytes)
Console.WriteLine()
Console.WriteLine("'{0}'", value)
Catch e As DecoderFallbackException
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index)
End Try
End Sub
Private Function ShowBytes(bytes As Byte()) As String
Dim returnString As String = Nothing
For Each byteValue In bytes
returnString += String.Format("0x{0:X2} ", byteValue)
Next
Return returnString.Trim()
End Function
End Module
' The example displays the following output:
' Unable to decode 0x01 0xD8 at index 4