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UTF7Encoding.GetDecoder Method

  • Reference

Definition

Namespace:
System.Text
Assemblies:
mscorlib.dll, System.Text.Encoding.Extensions.dll
Assembly:
System.Text.Encoding.Extensions.dll
Assembly:
mscorlib.dll
Assembly:
netstandard.dll
Source:
UTF7Encoding.cs
Source:
UTF7Encoding.cs
Source:
UTF7Encoding.cs

Obtains a decoder that converts a UTF-7 encoded sequence of bytes into a sequence of Unicode characters.

public:
 override System::Text::Decoder ^ GetDecoder();
public override System.Text.Decoder GetDecoder ();
override this.GetDecoder : unit -> System.Text.Decoder
Public Overrides Function GetDecoder () As Decoder

Returns

Decoder

A Decoder that converts a UTF-7 encoded sequence of bytes into a sequence of Unicode characters.

Examples

The following code example demonstrates how to use the GetDecoder method to obtain a decoder to convert the UTF-7 encoded bytes into a sequence of characters.

using namespace System;
using namespace System::Text;
using namespace System::Collections;
int main()
{
   array<Char>^chars;
   array<Byte>^bytes = {99,43,65,119,67,103,111,65,45};
   Decoder^ utf7Decoder = Encoding::UTF7->GetDecoder();
   int charCount = utf7Decoder->GetCharCount( bytes, 0, bytes->Length );
   chars = gcnew array<Char>(charCount);
   int charsDecodedCount = utf7Decoder->GetChars( bytes, 0, bytes->Length, 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 UTF7EncodingExample {
    public static void Main() {
        Char[] chars;
        Byte[] bytes = new Byte[] {
            99, 43, 65, 119, 67, 103, 111, 65, 45
        };

        Decoder utf7Decoder = Encoding.UTF7.GetDecoder();

        int charCount = utf7Decoder.GetCharCount(bytes, 0, bytes.Length);
        chars = new Char[charCount];
        int charsDecodedCount = utf7Decoder.GetChars(bytes, 0, bytes.Length, 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.Text

Class UTF7EncodingExample
    
    Public Shared Sub Main()
        Dim chars() As Char
        Dim bytes() As Byte = {99, 43, 65, 119, 67, 103, 111, 65, 45}
        
        Dim utf7Decoder As Decoder = Encoding.UTF7.GetDecoder()
        
        Dim charCount As Integer = utf7Decoder.GetCharCount(bytes, 0, bytes.Length)
        chars = New Char(charCount - 1) {}
        Dim charsDecodedCount As Integer = utf7Decoder.GetChars(bytes, 0, bytes.Length, 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

The Decoder.GetChars method converts sequential blocks of bytes into sequential blocks of characters, in a manner similar to the GetChars method of this class. However, a Decoder maintains state information between calls so it can correctly decode byte sequences that span blocks. The Decoder also preserves trailing bytes at the end of data blocks and uses the trailing bytes in the next decoding operation. Therefore, GetDecoder and GetEncoder are useful for network transmission and file operations, because those operations often deal with blocks of data instead of a complete data stream.

Applies to

See also