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UTF32Encoding.GetBytes Method (Char[], Int32, Int32, Byte[], Int32)

Encodes a set of characters from the specified character array into the specified byte array.

Namespace:  System.Text
Assembly:  mscorlib (in mscorlib.dll)
public override int GetBytes(
	char[] chars,
	int charIndex,
	int charCount,
	byte[] bytes,
	int byteIndex
)

Parameters

chars
Type: System.Char[]

The character array containing the set of characters to encode.

charIndex
Type: System.Int32

The index of the first character to encode.

charCount
Type: System.Int32

The number of characters to encode.

bytes
Type: System.Byte[]

The byte array to contain the resulting sequence of bytes.

byteIndex
Type: System.Int32

The index at which to start writing the resulting sequence of bytes.

Return Value

Type: System.Int32
The actual number of bytes written into bytes.
ExceptionCondition
ArgumentNullException

chars is null.

-or-

bytes is null.

ArgumentOutOfRangeException

charIndex or charCount or byteIndex is less than zero.

-or-

charIndex and charCount do not denote a valid range in chars.

-or-

byteIndex is not a valid index in bytes.

ArgumentException

Error detection is enabled, and chars contains an invalid sequence of characters.

-or-

bytes does not have enough capacity from byteIndex to the end of the array to accommodate the resulting bytes.

EncoderFallbackException

A fallback occurred (see Character Encoding in the .NET Framework for complete explanation)

-and-

EncoderFallback is set to EncoderExceptionFallback.

To calculate the exact array size required by GetBytes to store the resulting bytes, the application uses GetByteCount. To calculate the maximum array size, the application should use GetMaxByteCount. The GetByteCount method generally allows allocation of less memory, while the GetMaxByteCount method generally executes faster.

With error detection, an invalid sequence causes this method to throw a ArgumentException. Without error detection, invalid sequences are ignored, and no exception is thrown.

Data to be converted, such as data read from a stream, might be available only in sequential blocks. In this case, or if the amount of data is so large that it needs to be divided into smaller blocks, the application uses the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively.

NoteNote

To ensure that the encoded bytes are decoded properly, the application should prefix encoded bytes with a preamble.

The following code example determines the number of bytes required to encode three characters from a character array, then encodes the characters and displays the resulting bytes.

using System;
using System.Text;

public class SamplesUTF32Encoding  {

   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[7] { 'z', 'a', '\u0306', '\u01FD', '\u03B2', '\uD8FF', '\uDCFF' };

      // Create instances of different encodings.
      UTF7Encoding  u7       = new UTF7Encoding();
      UTF8Encoding  u8Nobom  = new UTF8Encoding( false, true );
      UTF8Encoding  u8Bom    = new UTF8Encoding( true,  true );
      UTF32Encoding u32Nobom = new UTF32Encoding( false, false, true );
      UTF32Encoding u32Bom   = new UTF32Encoding( false, true,  true );

      // 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, u8Nobom );
      PrintCountsAndBytes( myChars, 4, 3, u8Bom );
      PrintCountsAndBytes( myChars, 4, 3, u32Nobom );
      PrintCountsAndBytes( myChars, 4, 3, u32Bom );

   }


   public static void PrintCountsAndBytes( char[] chars, int index, int count, Encoding enc )  {

      // Display the name of the encoding used.
      Console.Write( "{0,-25} :", 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 );

      // Get the byte order mark, if any. 
      byte[] preamble = enc.GetPreamble();

      // Combine the preamble and the encoded bytes. 
      byte[] bytes = new byte[preamble.Length + iBC];
      Array.Copy( preamble, bytes, preamble.Length );
      enc.GetBytes( chars, index, count, bytes, preamble.Length );

      // 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.UTF8Encoding  : 6   12  :EF BB BF CE B2 F1 8F B3 BF
System.Text.UTF32Encoding : 8   12  :B2 03 00 00 FF FC 04 00
System.Text.UTF32Encoding : 8   12  :FF FE 00 00 B2 03 00 00 FF FC 04 00

*/

.NET Framework

Supported in: 4.5.1, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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