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Encoding.GetChars Method (Byte[], Int32, Int32)

When overridden in a derived class, decodes a sequence of bytes from the specified byte array into a set of characters.

Namespace: System.Text
Assembly: mscorlib (in mscorlib.dll)

'Declaration
Public Overridable Function GetChars ( _
	bytes As Byte(), _
	index As Integer, _
	count As Integer _
) As Char()
'Usage
Dim instance As Encoding
Dim bytes As Byte()
Dim index As Integer
Dim count As Integer
Dim returnValue As Char()

returnValue = instance.GetChars(bytes, index, count)
public char[] GetChars (
	byte[] bytes, 
	int index, 
	int count
)
public function GetChars (
	bytes : byte[], 
	index : int, 
	count : int
) : char[]

Parameters

bytes

The byte array containing the sequence of bytes to decode.

index

The index of the first byte to decode.

count

The number of bytes to decode.

Return Value

A character array containing the results of decoding the specified sequence of bytes.

Exception typeCondition

ArgumentNullException

bytes is a null reference (Nothing in Visual Basic).

ArgumentOutOfRangeException

index or count is less than zero.

-or-

index and count do not denote a valid range in bytes.

If the data to be converted is available only in sequential blocks (such as data read from a stream) or if the amount of data is so large that it needs to be divided into smaller blocks, use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively, of a derived class.

The following code example encodes a string into an array of bytes, and then decodes a range of the bytes into an array of characters.

Imports System
Imports System.Text
Imports Microsoft.VisualBasic

Public Class SamplesEncoding   

   Public Shared Sub Main()

      ' Create two instances of UTF32Encoding: one with little-endian byte order and one with big-endian byte order.
      Dim u32LE As Encoding = Encoding.GetEncoding("utf-32")
      Dim u32BE As Encoding = Encoding.GetEncoding("utf-32BE")

      ' Use a string containing the following characters:
      '    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)
      Dim myStr As String = "za" & ChrW(&H0306) & ChrW(&H01FD) & ChrW(&H03B2)

      ' Encode the string using the big-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrBE with the exact number of elements required.
      Dim barrBE(u32BE.GetByteCount(myStr) - 1) As Byte
      u32BE.GetBytes(myStr, 0, myStr.Length, barrBE, 0)

      ' Encode the string using the little-endian byte order.
      ' NOTE: In VB.NET, arrays contain one extra element by default.
      '       The following line creates barrLE with the exact number of elements required.
      Dim barrLE(u32LE.GetByteCount(myStr) - 1) As Byte
      u32LE.GetBytes(myStr, 0, myStr.Length, barrLE, 0)

      ' Get the char counts, decode eight bytes starting at index 0,
      ' and print out the counts and the resulting bytes.
      Console.Write("BE array with BE encoding : ")
      PrintCountsAndChars(barrBE, 0, 8, u32BE)
      Console.Write("LE array with LE encoding : ")
      PrintCountsAndChars(barrLE, 0, 8, u32LE)

   End Sub 'Main


   Public Shared Sub PrintCountsAndChars(bytes() As Byte, index As Integer, count As Integer, enc As Encoding)

      ' Display the name of the encoding used.
      Console.Write("{0,-25} :", enc.ToString())

      ' Display the exact character count.
      Dim iCC As Integer = enc.GetCharCount(bytes, index, count)
      Console.Write(" {0,-3}", iCC)

      ' Display the maximum character count.
      Dim iMCC As Integer = enc.GetMaxCharCount(count)
      Console.Write(" {0,-3} :", iMCC)

      ' Decode the bytes.
      Dim chars As Char() = enc.GetChars(bytes, index, count)

      ' The following is an alternative way to decode the bytes:
      ' 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 chars(iCC - 1) As Char
      ' enc.GetChars( bytes, index, count, chars, 0 )

      ' Display the characters.
      Console.WriteLine(chars)

   End Sub 'PrintCountsAndChars 

End Class 'SamplesEncoding


'This code produces the following output.  The question marks take the place of characters that cannot be displayed at the console.
'
'BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
'LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za


import System.*;
import System.Text.*;

public class SamplesEncoding
{
    public static void main(String[] args)
    {
        // Create two instances of UTF32Encoding: one with little-endian 
        // byte order and one with big-endian byte order.
        Encoding u32LE = Encoding.GetEncoding("utf-32");
        Encoding u32BE = Encoding.GetEncoding("utf-32BE");

        // Use a string containing the following characters:
        //    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)
        String myStr = "za\u0306\u01FD\u03B2";

        // Encode the string using the big-endian byte order.
        ubyte barrBE[] = new ubyte[u32BE.GetByteCount(myStr)];
        u32BE.GetBytes(myStr, 0, myStr.get_Length(), barrBE, 0);

        // Encode the string using the little-endian byte order.
        ubyte barrLE[] = new ubyte[u32LE.GetByteCount(myStr)];
        u32LE.GetBytes(myStr, 0, myStr.get_Length(), barrLE, 0);

        // Get the char counts, decode eight bytes starting at index 0,
        // and print out the counts and the resulting bytes.
        Console.Write("BE array with BE encoding : ");
        PrintCountsAndChars(barrBE, 0, 8, u32BE);
        Console.Write("LE array with LE encoding : ");
        PrintCountsAndChars(barrLE, 0, 8, u32LE);
    } //main

    public static void PrintCountsAndChars(ubyte bytes[], 
                    int index, int count, Encoding enc)
    {
        // Display the name of the encoding used.
        Console.Write("{0,-25} :", enc.ToString());

        // Display the exact character count.
        int iCC = enc.GetCharCount(bytes, index, count);
        Console.Write(" {0,-3}", String.valueOf(iCC));

        // Display the maximum character count.
        int iMCC = enc.GetMaxCharCount(count);
        Console.Write(" {0,-3} :", String.valueOf(iMCC));

        // Decode the bytes and display the characters.
        char chars[] = enc.GetChars(bytes, index, count);

        // The following is an alternative way to decode the bytes:
        // char[] chars = new char[iCC];
        // enc.GetChars( bytes, index, count, chars, 0 );
        Console.WriteLine(chars);
    } //PrintCountsAndChars
} //SamplesEncoding

/* 
This code produces the following output.  The question marks take the
 place of characters that cannot be displayed at the console.

BE array with BE encoding : System.Text.UTF32Encoding : 2   6   :za
LE array with LE encoding : System.Text.UTF32Encoding : 2   6   :za

*/


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

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

.NET Framework

Supported in: 2.0, 1.1, 1.0

.NET Compact Framework

Supported in: 2.0, 1.0

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