Encoding.UTF7 属性
获取 UTF-7 格式的编码。
**命名空间:**System.Text
**程序集:**mscorlib（在 mscorlib.dll 中）
语法
声明
Public Shared ReadOnly Property UTF7 As Encoding
用法
Dim value As Encoding
value = Encoding.UTF7
public static Encoding UTF7 { get; }
public:
static property Encoding^ UTF7 {
Encoding^ get ();
}
/** @property */
public static Encoding get_UTF7 ()
public static function get UTF7 () : Encoding
属性值
UTF-7 格式的 Encoding。
备注
Unicode 标准为所有支持脚本中的每个字符分配一个码位（一个数字）。Unicode 转换格式 (UTF) 是一种码位编码方式。Unicode 标准 3.2 版使用下列 UTF：
UTF-8，它将每个码位表示为一个由 1 至 4 个字节组成的序列。
UTF-16，它将每个码位表示为一个由 1 至 2 个 16 位整数组成的序列。
UTF-32，它将每个码位表示为一个 32 位整数。
有关 UTF 的更多信息，请参见 www.unicode.org 上的“The Unicode Standard”（Unicode 标准）部分。
示例
下面的代码示例在将字符串写入一个流之前，使用 UTF-7 对该字符串进行编码。
Imports System
Imports System.IO
Imports System.Text
Imports Microsoft.VisualBasic
Namespace UTF7Example
Public Class UTF7ExampleClass
Public Shared Sub Main()
Dim unicodeString As String = "This string contains the unicode character Pi(" & ChrW(&H03A0) & ")"
' Create a UTF7 encoding
Dim utf7 As Encoding = Encoding.UTF7
' Converting to UTF7 encodes characters so that they will pass through
' ASCII systems such as email.
Dim utf7Writer As New StreamWriter("output.txt", False, utf7)
utf7Writer.WriteLine(utf7.BodyName)
utf7Writer.WriteLine(unicodeString)
utf7Writer.Flush()
utf7Writer.Close()
End Sub
End Class
End Namespace
using System;
using System.IO;
using System.Text;
namespace UTF7Example
{
public class UTF7ExampleClass
{
public static void Main()
{
string unicodeString = "This string contains the unicode character Pi(\u03a0)";
// Create a UTF7 encoding
Encoding utf7 = Encoding.UTF7;
// Converting to UTF7 encodes characters so that they will pass through
// ASCII systems such as email.
StreamWriter utf7Writer = new StreamWriter("output.txt", false, utf7);
utf7Writer.WriteLine(utf7.BodyName);
utf7Writer.WriteLine(unicodeString);
utf7Writer.Flush();
utf7Writer.Close();
}
}
}
using namespace System;
using namespace System::IO;
using namespace System::Text;
int main()
{
String^ unicodeString = "This string contains the unicode character Pi(\u03a0)";
// Create a UTF7 encoding
Encoding^ utf7 = Encoding::UTF7;
// Converting to UTF7 encodes characters so that they will pass through
// ASCII systems such as email.
StreamWriter^ utf7Writer = gcnew StreamWriter( "output.txt",false,utf7 );
utf7Writer->WriteLine( utf7->BodyName );
utf7Writer->WriteLine( unicodeString );
utf7Writer->Flush();
utf7Writer->Close();
}
package UTF7Example;
import System.*;
import System.IO.*;
import System.Text.*;
public class UTF7ExampleClass
{
public static void main(String[] args)
{
String unicodeString =
"This string contains the unicode character Pi(\u03a0)";
// Create a UTF7 encoding
Encoding utf7 = Encoding.get_UTF7();
// Converting to UTF7 encodes characters so that they will pass through
// ASCII systems such as email.
StreamWriter utf7Writer = new StreamWriter("output.txt", false, utf7);
utf7Writer.WriteLine(utf7.get_BodyName());
utf7Writer.WriteLine(unicodeString);
utf7Writer.Flush();
utf7Writer.Close();
} //main
} //UTF7ExampleClass
下面的代码示例确定了对一个字符数组进行编码所需的字节数，然后对这些字符进行编码，并显示所产生的字节。
Imports System
Imports System.Text
Imports Microsoft.VisualBasic
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 'Main
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 'PrintCountsAndBytes
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 'PrintHexBytes
End Class 'SamplesEncoding
'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
*/
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
*/
import System.*;
import System.Text.*;
import System.Byte;
public class SamplesEncoding
{
public static void main(String[] args)
{
// 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.get_UTF7();
Encoding u8 = Encoding.get_UTF8();
Encoding u16LE = Encoding.get_Unicode();
Encoding u16BE = Encoding.get_BigEndianUnicode();
Encoding u32 = Encoding.get_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);
} //main
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}", String.valueOf(iBC));
// Display the maximum byte count.
int iMBC = enc.GetMaxByteCount(chars.length);
Console.Write(" {0,-3} :", String.valueOf(iMBC));
// Encode the array of chars.
ubyte bytes[] = enc.GetBytes(chars);
// Display all the encoded bytes.
PrintHexBytes(bytes);
} //PrintCountsAndBytes
public static void PrintHexBytes(ubyte bytes[])
{
if(bytes == null || bytes.length == 0) {
Console.WriteLine("<none>");
}
else {
for(int i = 0; i < bytes.length; i++) {
Console.Write("{0:X2} ",
((System.Byte)bytes[i]).ToString("X2"));
}
Console.WriteLine();
}
} //PrintHexBytes
} //SamplesEncoding
/*
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
*/
平台
Windows 98、Windows 2000 SP4、Windows CE、Windows Millennium Edition、Windows Mobile for Pocket PC、Windows Mobile for Smartphone、Windows Server 2003、Windows XP Media Center Edition、Windows XP Professional x64 Edition、Windows XP SP2、Windows XP Starter Edition
.NET Framework 并不是对每个平台的所有版本都提供支持。有关受支持版本的列表，请参见系统要求。
版本信息
.NET Framework
受以下版本支持：2.0、1.1、1.0
.NET Compact Framework
受以下版本支持：2.0、1.0
请参见
参考
Encoding 类
Encoding 成员
System.Text 命名空间
UTF7Encoding
GetEncoding
Encoding.Default 属性
Encoding.ASCII 属性
UTF8
Encoding.Unicode 属性
Encoding.BigEndianUnicode 属性
Encoding.UTF32 属性