Encoding.GetBytes 方法

参考

定义

命名空间:: System.Text

程序集:: System.Text.Encoding.dll

程序集:: System.Runtime.dll

程序集:: netstandard.dll

程序集:: mscorlib.dll

重要

一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。

在派生类中重写时，将一组字符编码为一个字节序列。

重载

GetBytes(Char[])	在派生类中重写时，将指定字符数组中的所有字符编码为一个字节序列。
GetBytes(String)	在派生类中重写时，将指定字符串中的所有字符编码为一个字节序列。
GetBytes(ReadOnlySpan<Char>, Span<Byte>)	在派生类中重写时，将指定只读范围中的一组字符编码为字节范围。
GetBytes(Char[], Int32, Int32)	在派生类中重写时，将指定字符数组中的一组字符编码为一个字节序列。
GetBytes(String, Int32, Int32)	在派生类中重写时，从指定的 `index` 开始，将指定字符串中由 `count` 指定的字符数编码为字节数组。
GetBytes(Char, Int32, Byte, Int32)	在派生类中重写时，将一组字符（从指定的字符指针开始）编码为一个字节序列，并从指定的字节指针开始存储该字节序列。
GetBytes(Char[], Int32, Int32, Byte[], Int32)	在派生类中重写时，将指定字符数组中的一组字符编码为指定的字节数组。
GetBytes(String, Int32, Int32, Byte[], Int32)	在派生类中重写时，将指定字符串中的一组字符编码为指定的字节数组。

GetBytes(Char[])

在派生类中重写时，将指定字符数组中的所有字符编码为一个字节序列。

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()

参数

chars: Char[]

包含要编码的字符的字符数组。

Byte[]

一个字节数组，包含对指定的字符集进行编码的结果。

例外

ArgumentNullException

chars 上声明的默认值为 null。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

示例

下面的示例确定对字符数组进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

如果要转换的数据仅在顺序块（如从流中读取的数据）中可用，或者如果数据量很大以致需要分为更小块，则应使用 Decoder Encoder GetDecoder 派生类的方法或方法提供的或 GetEncoder 。

GetByteCount方法确定导致对一组 Unicode 字符进行编码的字节数， GetBytes 方法执行实际编码。 GetBytes方法需要离散转换，这与方法不同， Encoder.GetBytes 后者处理单个输入流上的多个转换。

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应调用该方法的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

GetBytes(String)

在派生类中重写时，将指定字符串中的所有字符编码为一个字节序列。

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()

参数

s: String

包含要编码的字符的字符串。

Byte[]

一个字节数组，包含对指定的字符集进行编码的结果。

例外

ArgumentNullException

s 上声明的默认值为 null。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

示例

下面的示例确定了对字符串中的字符串或范围进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

GetByteCount方法确定导致对一组 Unicode 字符进行编码的字节数， GetBytes 方法执行实际编码。 Encoding.GetBytes方法需要离散转换，这与方法不同， Encoder.GetBytes 后者处理单个输入流上的多个转换。

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

GetBytes(ReadOnlySpan<Char>, Span<Byte>)

在派生类中重写时，将指定只读范围中的一组字符编码为字节范围。

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

参数

chars: ReadOnlySpan<Char>

包含要编码的字符集的范围。

bytes: Span<Byte>

用于保存已编码字节的字节范围。

Int32

已编码的字节数。

注解

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

适用于

GetBytes(Char[], Int32, Int32)

在派生类中重写时，将指定字符数组中的一组字符编码为一个字节序列。

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()

参数

chars: Char[]

包含要编码的字符集的字符数组。

index: Int32

第一个要编码的字符的索引。

count: Int32

要编码的字符的数目。

Byte[]

一个字节数组，包含对指定的字符集进行编码的结果。

例外

ArgumentNullException

chars 上声明的默认值为 null。

ArgumentOutOfRangeException

index 或 count 小于零。

或 -

index 和 count 不表示 chars 中的有效范围。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

示例

下面的示例确定对字符数组中的三个字符进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

GetBytes(String, Int32, Int32)

在派生类中重写时，从指定的 index 开始，将指定字符串中由 count 指定的字符数编码为字节数组。

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()

参数

s: String

包含要编码的字符的字符串。

index: Int32

字符串内的索引，要从该位置开始编码。

count: Int32

要编码的字符的数目。

Byte[]

一个字节数组，包含对指定的字符集进行编码的结果。

示例

下面的示例确定了对字符串中的字符串或范围进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

适用于

GetBytes(Char, Int32, Byte, Int32)

重要

此 API 不符合 CLS。

在派生类中重写时，将一组字符（从指定的字符指针开始）编码为一个字节序列，并从指定的字节指针开始存储该字节序列。

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);

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

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

参数

chars: Char*

指向第一个要编码的字符的指针。

charCount: Int32

要编码的字符的数目。

bytes: Byte*

一个指针，指向开始写入所产生的字节序列的位置。

byteCount: Int32

最多写入的字节数。

Int32

在由 bytes 参数指示的位置处写入的实际字节数。

属性: CLSCompliantAttribute SecurityCriticalAttribute ComVisibleAttribute

例外

ArgumentNullException

chars 上声明的默认值为 null。

或 -

bytes 上声明的默认值为 null。

ArgumentOutOfRangeException

charCount 或 byteCount 小于零。

ArgumentException

byteCount 少于所产生的字节数。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

注解

若要计算 GetBytes 存储生成的字节所需的确切数组大小，请调用 GetByteCount 方法。若要计算最大数组大小，请调用 GetMaxByteCount 方法。 GetByteCount方法通常允许分配较少的内存，而 GetMaxByteCount 方法的执行速度通常更快。

如果要转换的数据仅在（如从流中读取的数据）的顺序块中可用，或者如果数据量很大，它需要划分为较小的块，则应使用Decoder或Encoder提供对象GetDecoder或GetEncoder方法，分别的派生类。

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

GetBytes(Char[], Int32, Int32, Byte[], Int32)

在派生类中重写时，将指定字符数组中的一组字符编码为指定的字节数组。

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

参数

chars: Char[]

包含要编码的字符集的字符数组。

charIndex: Int32

第一个要编码的字符的索引。

charCount: Int32

要编码的字符的数目。

bytes: Byte[]

要包含所产生的字节序列的字节数组。

byteIndex: Int32

要开始写入所产生的字节序列的索引位置。

Int32

写入 bytes 的实际字节数。

例外

ArgumentNullException

chars 上声明的默认值为 null。

或 -

bytes 上声明的默认值为 null。

ArgumentOutOfRangeException

charIndex、charCount 或 byteIndex 小于零。

或 -

charIndex 和 charCount 不表示 chars中的有效范围。

或 -

byteIndex 不是 bytes 中的有效索引。

ArgumentException

bytes 中从 byteIndex 到数组结尾没有足够的容量来容纳所产生的字节。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

示例

下面的示例确定对字符数组中的三个字符进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

若要计算存储生成的字节所需的确切数组大小 GetBytes ，应调用 GetByteCount 方法。若要计算最大数组大小，请调用 GetMaxByteCount 方法。 GetByteCount方法通常允许分配较少的内存，而 GetMaxByteCount 方法的执行速度通常更快。

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

GetBytes(String, Int32, Int32, Byte[], Int32)

在派生类中重写时，将指定字符串中的一组字符编码为指定的字节数组。

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

参数

s: String

包含要编码的字符集的字符串。

charIndex: Int32

第一个要编码的字符的索引。

charCount: Int32

要编码的字符的数目。

bytes: Byte[]

要包含所产生的字节序列的字节数组。

byteIndex: Int32

要开始写入所产生的字节序列的索引位置。

Int32

写入 bytes 的实际字节数。

例外

ArgumentNullException

s 上声明的默认值为 null。

或 -

bytes 上声明的默认值为 null。

ArgumentOutOfRangeException

charIndex、charCount 或 byteIndex 小于零。

或 -

charIndex 和 charCount 不表示 chars中的有效范围。

或 -

byteIndex 不是 bytes 中的有效索引。

ArgumentException

bytes 中从 byteIndex 到数组结尾没有足够的容量来容纳所产生的字节。

EncoderFallbackException

发生回退（有关详细信息，请参阅采用 .NET 的字符编码）

－和－

将 EncoderFallback 设置为 EncoderExceptionFallback。

示例

下面的示例确定了对字符串中的字符串或范围进行编码、对字符进行编码并显示生成的字节所需的字节数。

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

注解

支持和的多个版本 GetByteCount GetBytes 。下面是有关使用这些方法的一些编程注意事项：

您的应用程序可能需要将许多输入字符编码为代码页，并使用多个调用处理这些字符。在这种情况下，您可能需要维护两次调用之间的状态，同时考虑所使用的对象保留的状态 Encoder 。（例如，包含代理项对的字符序列可能以高代理项结束。 Encoder将记住高代理项，以便可以在以下调用开始时将其与低代理项组合在一起。 Encoding无法维护状态，因此字符将发送到 EncoderFallback 。）
如果你的应用程序处理字符串输入，则应使用的字符串版本 GetBytes 。
的 Unicode 字符缓冲区版本 GetBytes(Char*, Int32, Byte*, Int32) 允许一些快速的技巧，尤其是使用对象的多个调用 Encoder 或插入现有缓冲区。但请记住，此方法版本有时不安全，因为指针是必需的。
如果你的应用程序必须转换大量数据，则应重新使用输出缓冲区。在这种情况下， GetBytes 支持字节数组的版本是最佳选择。
请考虑使用 Encoder.Convert 方法而不是 GetByteCount 。转换方法可转换尽可能多的数据，如果输出缓冲区太小，则会引发异常。对于流的连续编码，此方法通常是最佳选择。

另请参阅

适用于

Encoding.GetBytes 方法

定义

重载

GetBytes(Char[])

参数

返回

例外

示例

注解

另请参阅

适用于

GetBytes(String)

参数

返回

例外

示例

注解

另请参阅

适用于

GetBytes(ReadOnlySpan<Char>, Span<Byte>)

参数

返回

注解

适用于

GetBytes(Char[], Int32, Int32)

参数

返回

例外

示例

注解

另请参阅

适用于

GetBytes(String, Int32, Int32)

参数

返回

示例

注解

适用于

GetBytes(Char*, Int32, Byte*, Int32)

参数

返回

例外

注解

另请参阅

适用于

GetBytes(Char[], Int32, Int32, Byte[], Int32)

参数

返回

例外

示例

注解

另请参阅

适用于

GetBytes(String, Int32, Int32, Byte[], Int32)

参数

返回

例外

示例

注解

另请参阅

适用于

其他资源

GetBytes(Char, Int32, Byte, Int32)