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UTF7 Property

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 property Encoding^ UTF7 {
	Encoding^ 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 namespace System;
using namespace System::Text;
void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc );
void PrintHexBytes( array<Byte>^bytes );
int 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) 
   array<Char>^myChars = gcnew array<Char>{
      L'z','a',L'\u0306',L'\u01FD',L'\u03B2',L'\xD8FF',L'\xDCFF'
   };

   // 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 );
}

void PrintCountsAndBytes( array<Char>^chars, Encoding^ enc )
{

   // Display the name of the encoding used.
   Console::Write( "{0,-30} :", enc );

   // 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. 
   array<Byte>^bytes = enc->GetBytes( chars );

   // Display all the encoded bytes.
   PrintHexBytes( bytes );
}

void PrintHexBytes( array<Byte>^bytes )
{
   if ( (bytes == nullptr) || (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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