Encoding.BigEndianUnicode Property
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Gets an encoding for the UTF-16 format that uses the big endian byte order.
public:
static property System::Text::Encoding ^ BigEndianUnicode { System::Text::Encoding ^ get(); };public static System.Text.Encoding BigEndianUnicode { get; }static member BigEndianUnicode : System.Text.EncodingPublic Shared ReadOnly Property BigEndianUnicode As EncodingProperty Value
An encoding object for the UTF-16 format that uses the big endian byte order.
Examples
The following example reads a text file with a UTF-16 encoding using the big endian byte order.
using namespace System;
using namespace System::IO;
int main()
{
// Read a text file saved with Big Endian Unicode encoding.
System::Text::Encoding^ encoding = System::Text::Encoding::BigEndianUnicode;
StreamReader^ reader = gcnew StreamReader( "TextFile.txt",encoding );
String^ line = reader->ReadLine();
while ( line != nullptr )
{
Console::WriteLine( line );
line = reader->ReadLine();
}
}
using System;
using System.IO;
namespace BigEndianExample
{
public class Class1
{
public static void Main(string[] args)
{
// Read a text file saved with Big Endian Unicode encoding.
System.Text.Encoding encoding = System.Text.Encoding.BigEndianUnicode;
StreamReader reader = new StreamReader("TextFile.txt", encoding);
string line = reader.ReadLine();
while (line != null)
{
Console.WriteLine(line);
line = reader.ReadLine();
}
}
}
}
Imports System.IO
Namespace BigEndianExample
Public Class Class1
Public Overloads Shared Sub Main()
' Read a text file saved with Big Endian Unicode encoding.
Dim encoding As System.Text.Encoding = System.Text.Encoding.BigEndianUnicode
Dim reader As New StreamReader("TextFile.txt", encoding)
Dim line As String = reader.ReadLine()
While Not (line Is Nothing)
Console.WriteLine(line)
line = reader.ReadLine()
End While
End Sub
End Class
End Namespace
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
*/
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
*/
Imports System.Text
Public Class SamplesEncoding
Public Shared Sub 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)
Dim myChars() As Char = {"z"c, "a"c, ChrW(&H0306), ChrW(&H01FD), ChrW(&H03B2), ChrW(&HD8FF), ChrW(&HDCFF)}
' Get different encodings.
Dim u7 As Encoding = Encoding.UTF7
Dim u8 As Encoding = Encoding.UTF8
Dim u16LE As Encoding = Encoding.Unicode
Dim u16BE As Encoding = Encoding.BigEndianUnicode
Dim u32 As Encoding = 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)
End Sub
Public Shared Sub PrintCountsAndBytes(chars() As Char, enc As Encoding)
' Display the name of the encoding used.
Console.Write("{0,-30} :", enc.ToString())
' Display the exact byte count.
Dim iBC As Integer = enc.GetByteCount(chars)
Console.Write(" {0,-3}", iBC)
' Display the maximum byte count.
Dim iMBC As Integer = enc.GetMaxByteCount(chars.Length)
Console.Write(" {0,-3} :", iMBC)
' Encode the array of chars.
Dim bytes As Byte() = enc.GetBytes(chars)
' Display all the encoded bytes.
PrintHexBytes(bytes)
End Sub
Public Shared Sub PrintHexBytes(bytes() As Byte)
If bytes Is Nothing OrElse bytes.Length = 0 Then
Console.WriteLine("<none>")
Else
Dim i As Integer
For i = 0 To bytes.Length - 1
Console.Write("{0:X2} ", bytes(i))
Next i
Console.WriteLine()
End If
End Sub
End Class
'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
Remarks
The UnicodeEncoding object that is returned by this property may not have the appropriate behavior for your app. It uses replacement fallback to replace each string that it cannot encode and each byte that it cannot decode with a question mark ("?") character. Instead, you can call the UnicodeEncoding.UnicodeEncoding(Boolean, Boolean, Boolean) constructor to instantiate a big endian UnicodeEncoding object whose fallback is either an EncoderFallbackException or a DecoderFallbackException, as the following example illustrates.
using System;
using System.Text;
public class Example
{
public static void Main()
{
byte[] bytes = { 0x00, 0x20, 0xd8, 0x01, 0x00, 0x68, 0xA7, 0x00 };
Encoding enc = new UnicodeEncoding(true, true, true);
try {
string value = enc.GetString(bytes);
Console.WriteLine();
Console.WriteLine("'{0}'", value);
}
catch (DecoderFallbackException e) {
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index);
}
}
private static string ShowBytes(byte[] bytes)
{
string returnString = null;
foreach (var byteValue in bytes)
returnString += String.Format("0x{0:X2} ", byteValue);
return returnString.Trim();
}
}
// The example displays the following output:
// Unable to decode 0xD8 0x01 at index 4
Imports System.Text
Module Example
Public Sub Main()
Dim bytes() As Byte = { &h00, &h20, &hd8, &h01, &h00, &h68, &hA7, &h00}
Dim enc As Encoding = New UnicodeEncoding(True, True, True)
Try
Dim value As String = enc.GetString(bytes)
Console.WriteLine()
Console.WriteLine("'{0}'", value)
Catch e As DecoderFallbackException
Console.WriteLine("Unable to decode {0} at index {1}",
ShowBytes(e.BytesUnknown), e.Index)
End Try
End Sub
Private Function ShowBytes(bytes As Byte()) As String
Dim returnString As String = Nothing
For Each byteValue In bytes
returnString += String.Format("0x{0:X2} ", byteValue)
Next
Return returnString.Trim()
End Function
End Module
' The example displays the following output:
' Unable to decode 0xD8 0x01 at index 4
The returned UnicodeEncoding object has BodyName, HeaderName, and WebName properties, which yield the name "unicodeFFFE". Although the UTF-16 big endian byte order mark is hexadecimal FEFF, the name "unicodeFFFE" was chosen because the byte order mark appears as hexadecimal FFFE on little endian Windows computers.
Applies to
See also
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