ASCIIEncoding.GetChars Method

Definition

Overloads

GetChars(Byte*, Int32, Char*, Int32)

Decodes a sequence of bytes starting at the specified byte pointer into a set of characters that are stored starting at the specified character pointer.

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

Decodes a sequence of bytes from the specified byte array into the specified character array.

GetChars(Byte*, Int32, Char*, Int32)

This API is not CLS-compliant.

CLS-compliant alternative
System.Text.ASCIIEncoding.GetChars(Byte[], Int32, Int32, Char[], Int32)

Decodes a sequence of bytes starting at the specified byte pointer into a set of characters that are stored starting at the specified character pointer.

[System.CLSCompliant(false)]
[System.Runtime.InteropServices.ComVisible(false)]
[System.Security.SecurityCritical]
public override int GetChars (byte* bytes, int byteCount, char* chars, int charCount);
Parameters
bytes
Byte*

A pointer to the first byte to decode.

byteCount
Int32

The number of bytes to decode.

chars
Char*

A pointer to the location at which to start writing the resulting set of characters.

charCount
Int32

The maximum number of characters to write.

Returns

The actual number of characters written at the location indicated by chars.

Exceptions

bytes is null.

-or-

chars is null.

byteCount or charCount is less than zero.

charCount is less than the resulting number of characters.

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

-and-

DecoderFallback is set to DecoderExceptionFallback.

Remarks

To calculate the exact array size required by GetChars to store the resulting characters, the application uses GetCharCount. To calculate the maximum array size, the application should use GetMaxCharCount. The GetCharCount method generally allows allocation of less memory, while the GetMaxCharCount method generally executes faster.

Data to be converted, such as data read from a stream, can 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 should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively.

ASCIIEncoding does not provide error detection. Any byte greater than hexadecimal 0x7F is decoded as the Unicode question mark ("?").

Caution

For security reasons, your application is recommended to use UTF8Encoding, UnicodeEncoding, or UTF32Encoding and enable error detection.

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

Decodes a sequence of bytes from the specified byte array into the specified character array.

public override int GetChars (byte[] bytes, int byteIndex, int byteCount, char[] chars, int charIndex);
Parameters
bytes
Byte[]

The byte array containing the sequence of bytes to decode.

byteIndex
Int32

The index of the first byte to decode.

byteCount
Int32

The number of bytes to decode.

chars
Char[]

The character array to contain the resulting set of characters.

charIndex
Int32

The index at which to start writing the resulting set of characters.

Returns

The actual number of characters written into chars.

Exceptions

bytes is null.

-or-

chars is null.

byteIndex or byteCount or charIndex is less than zero.

-or-

byteindex and byteCount do not denote a valid range in bytes.

-or-

charIndex is not a valid index in chars.

chars does not have enough capacity from charIndex to the end of the array to accommodate the resulting characters.

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

-and-

DecoderFallback is set to DecoderExceptionFallback.

Examples

The following example demonstrates how to decode a range of elements from a byte array and store the result in a set of elements in a Unicode character array.

using namespace System;
using namespace System::Text;
using namespace System::Collections;
int main()
{
   array<Char>^chars;
   array<Byte>^bytes = {65,83,67,73,73,32,69,110,99,111,100,105,110,103,32,69,120,97,109,112,108,101};
   ASCIIEncoding^ ascii = gcnew ASCIIEncoding;
   int charCount = ascii->GetCharCount( bytes, 6, 8 );
   chars = gcnew array<Char>(charCount);
   int charsDecodedCount = ascii->GetChars( bytes, 6, 8, chars, 0 );
   Console::WriteLine( "{0} characters used to decode bytes.", charsDecodedCount );
   Console::Write( "Decoded chars: " );
   IEnumerator^ myEnum = chars->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      Char c = safe_cast<Char>(myEnum->Current);
      Console::Write( "[{0}]", c.ToString() );
   }

   Console::WriteLine();
}

using System;
using System.Text;

class ASCIIEncodingExample {
    public static void Main() {
        Char[] chars;
        Byte[] bytes = new Byte[] {
             65,  83,  67,  73,  73,  32,  69,
            110,  99, 111, 100, 105, 110, 103,
             32,  69, 120,  97, 109, 112, 108, 101
        };

        ASCIIEncoding ascii = new ASCIIEncoding();

        int charCount = ascii.GetCharCount(bytes, 6, 8);
        chars = new Char[charCount];
        int charsDecodedCount = ascii.GetChars(bytes, 6, 8, chars, 0);

        Console.WriteLine(
            "{0} characters used to decode bytes.", charsDecodedCount
        );

        Console.Write("Decoded chars: ");
        foreach (Char c in chars) {
            Console.Write("[{0}]", c);
        }
        Console.WriteLine();
    }
}
Imports System
Imports System.Text

Class ASCIIEncodingExample
    Public Shared Sub Main()
        Dim chars() As Char
        Dim bytes() As Byte = { _
             65,  83,  67,  73,  73,  32,  69, _
            110,  99, 111, 100, 105, 110, 103, _
             32,  69, 120,  97, 109, 112, 108, 101}

        Dim ascii As New ASCIIEncoding()

        Dim charCount As Integer = ascii.GetCharCount(bytes, 6, 8)
        chars = New Char(charCount - 1) {}
        Dim charsDecodedCount As Integer = ascii.GetChars(bytes, 6, 8, chars, 0)

        Console.WriteLine("{0} characters used to decode bytes.", charsDecodedCount)

        Console.Write("Decoded chars: ")
        Dim c As Char
        For Each c In chars
            Console.Write("[{0}]", c)
        Next c
        Console.WriteLine()
    End Sub
End Class

Remarks

To calculate the exact array size required by GetChars to store the resulting characters, the application uses GetCharCount. To calculate the maximum array size, the application should use GetMaxCharCount. The GetCharCount method generally allows allocation of less memory, while the GetMaxCharCount method generally executes faster.

Data to be converted, such as data read from a stream, can 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 should use the Decoder or the Encoder provided by the GetDecoder method or the GetEncoder method, respectively.

ASCIIEncoding does not provide error detection. Any byte greater than hexadecimal 0x7F is decoded as the Unicode question mark ("?").

Caution

For security reasons, your application is recommended to use UTF8Encoding, UnicodeEncoding, or UTF32Encoding and enable error detection.