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Encoding.UTF7 Property

Gets an encoding for the UTF-7 format.

Namespace:  System.Text
Assemblies:   System.Text.Encoding (in System.Text.Encoding.dll)
  mscorlib (in mscorlib.dll)

public static Encoding UTF7 { get; }

Property Value

Type: System.Text.Encoding
An encoding for the UTF-7 format.

UTF-7 encoding is used primarily in environments that historically have been restricted to 7 bits, such as NNTP and some email applications. Because of issues with robustness and security, you should not use UTF7 encoding in 8-bit environments where UTF-8 encoding can be used instead.

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

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

*/

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0
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