IdnMapping.GetUnicode Method

Definition

Decodes one or more domain name labels encoded according to the IDNA standard to a string of Unicode characters.

Overloads

GetUnicode(String)

Decodes a string of one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

GetUnicode(String, Int32)

Decodes a substring of one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

GetUnicode(String, Int32, Int32)

Decodes a substring of a specified length that contains one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

GetUnicode(String)

Decodes a string of one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

public:
 System::String ^ GetUnicode(System::String ^ ascii);
public string GetUnicode (string ascii);
member this.GetUnicode : string -> string
Public Function GetUnicode (ascii As String) As String

Parameters

ascii
String

The string to decode, which consists of one or more labels in the US-ASCII character range (U+0020 to U+007E) encoded according to the IDNA standard.

Returns

The Unicode equivalent of the IDNA substring specified by the ascii parameter.

Exceptions

ascii is null.

ascii is invalid based on the AllowUnassigned and UseStd3AsciiRules properties, and the IDNA standard.

Examples

The following example uses the GetAscii(String) method to convert an array of internationalized domain names to Punycode. The GetUnicode(String) method then converts the Punycode domain name back into the original domain name, but replaces the original label separators with the standard label separator.

using System;
using System.Globalization;

public class Example
{
   public static void Main()
   {
      string[] names = { "bücher.com", "мойдомен.рф", "παράδειγμα.δοκιμή",
                         "mycharity\u3002org",
                         "prose\u0000ware.com", "proseware..com", "a.org",
                         "my_company.com" };
      IdnMapping idn = new IdnMapping();

      foreach (var name in names) {
         try {
            string punyCode = idn.GetAscii(name);
            string name2 = idn.GetUnicode(punyCode);
            Console.WriteLine("{0} --> {1} --> {2}", name, punyCode, name2);
            Console.WriteLine("Original: {0}", ShowCodePoints(name));
            Console.WriteLine("Restored: {0}", ShowCodePoints(name2));
         }
         catch (ArgumentException) {
            Console.WriteLine("{0} is not a valid domain name.", name);
         }
         Console.WriteLine();
      }
   }

   private static string ShowCodePoints(string str1)
   {
      string output = "";
      foreach (var ch in str1)
         output += $"U+{(ushort)ch:X4} ";

      return output;
   }
}
// The example displays the following output:
//    bücher.com --> xn--bcher-kva.com --> bücher.com
//    Original: U+0062 U+00FC U+0063 U+0068 U+0065 U+0072 U+002E U+0063 U+006F U+006D
//    Restored: U+0062 U+00FC U+0063 U+0068 U+0065 U+0072 U+002E U+0063 U+006F U+006D
//
//    мойдомен.рф --> xn--d1acklchcc.xn--p1ai --> мойдомен.рф
//    Original: U+043C U+043E U+0439 U+0434 U+043E U+043C U+0435 U+043D U+002E U+0440 U+0444
//    Restored: U+043C U+043E U+0439 U+0434 U+043E U+043C U+0435 U+043D U+002E U+0440 U+0444
//
//    παράδειγμα.δοκιμή --> xn--hxajbheg2az3al.xn--jxalpdlp --> παράδειγμα.δοκιμή
//    Original: U+03C0 U+03B1 U+03C1 U+03AC U+03B4 U+03B5 U+03B9 U+03B3 U+03BC U+03B1 U+002E U+03B4 U+03BF U+03BA U+03B9 U+03BC U+03AE
//    Restored: U+03C0 U+03B1 U+03C1 U+03AC U+03B4 U+03B5 U+03B9 U+03B3 U+03BC U+03B1 U+002E U+03B4 U+03BF U+03BA U+03B9 U+03BC U+03AE
//
//    mycharity。org --> mycharity.org --> mycharity.org
//    Original: U+006D U+0079 U+0063 U+0068 U+0061 U+0072 U+0069 U+0074 U+0079 U+3002 U+006F U+0072 U+0067
//    Restored: U+006D U+0079 U+0063 U+0068 U+0061 U+0072 U+0069 U+0074 U+0079 U+002E U+006F U+0072 U+0067
//
//    prose ware.com is not a valid domain name.
//
//    proseware..com is not a valid domain name.
//
//    a.org --> a.org --> a.org
//    Original: U+0061 U+002E U+006F U+0072 U+0067
//    Restored: U+0061 U+002E U+006F U+0072 U+0067
//
//    my_company.com --> my_company.com --> my_company.com
//    Original: U+006D U+0079 U+005F U+0063 U+006F U+006D U+0070 U+0061 U+006E U+0079 U+002E U+0063 U+006F U+006D
//    Restored: U+006D U+0079 U+005F U+0063 U+006F U+006D U+0070 U+0061 U+006E U+0079 U+002E U+0063 U+006F U+006D
Imports System.Globalization

Module Example
   Public Sub Main()
      Dim names() As String = { "bücher.com", "мойдомен.рф", "παράδειγμα.δοκιμή",
                                "mycharity" + ChrW(&h3002) + "org",
                                "prose" + ChrW(0) + "ware.com", "proseware..com", "a.org", 
                                "my_company.com" }
      Dim idn As New IdnMapping()
      
      For Each name In names
         Try
            Dim punyCode As String = idn.GetAscii(name)
            Dim name2 As String = idn.GetUnicode(punyCode)
            Console.WriteLine("{0} --> {1} --> {2}", name, punyCode, name2) 
            Console.WriteLine("Original: {0}", ShowCodePoints(name))
            Console.WriteLine("Restored: {0}", ShowCodePoints(name2))
         Catch e As ArgumentException 
            Console.WriteLine("{0} is not a valid domain name.", name)
         End Try
         Console.WriteLine()
      Next   
   End Sub
   
   Private Function ShowCodePoints(str1 As String) As String
      Dim output As String = ""
      For Each ch In str1
         output += String.Format("U+{0} ", Convert.ToUInt16(ch).ToString("X4"))
      Next
      Return output
   End Function
End Module
' The example displays the following output:
'    bücher.com --> xn--bcher-kva.com --> bücher.com
'    Original: U+0062 U+00FC U+0063 U+0068 U+0065 U+0072 U+002E U+0063 U+006F U+006D
'    Restored: U+0062 U+00FC U+0063 U+0068 U+0065 U+0072 U+002E U+0063 U+006F U+006D
'    
'    мойдомен.рф --> xn--d1acklchcc.xn--p1ai --> мойдомен.рф
'    Original: U+043C U+043E U+0439 U+0434 U+043E U+043C U+0435 U+043D U+002E U+0440 U+0444
'    Restored: U+043C U+043E U+0439 U+0434 U+043E U+043C U+0435 U+043D U+002E U+0440 U+0444
'    
'    παράδειγμα.δοκιμή --> xn--hxajbheg2az3al.xn--jxalpdlp --> παράδειγμα.δοκιμή
'    Original: U+03C0 U+03B1 U+03C1 U+03AC U+03B4 U+03B5 U+03B9 U+03B3 U+03BC U+03B1 U+002E U+03B4 U+03BF U+03BA U+03B9 U+03BC U+03AE
'    Restored: U+03C0 U+03B1 U+03C1 U+03AC U+03B4 U+03B5 U+03B9 U+03B3 U+03BC U+03B1 U+002E U+03B4 U+03BF U+03BA U+03B9 U+03BC U+03AE
'    
'    mycharity。org --> mycharity.org --> mycharity.org
'    Original: U+006D U+0079 U+0063 U+0068 U+0061 U+0072 U+0069 U+0074 U+0079 U+3002 U+006F U+0072 U+0067
'    Restored: U+006D U+0079 U+0063 U+0068 U+0061 U+0072 U+0069 U+0074 U+0079 U+002E U+006F U+0072 U+0067
'    
'    prose ware.com is not a valid domain name.
'    
'    proseware..com is not a valid domain name.
'    
'    a.org --> a.org --> a.org
'    Original: U+0061 U+002E U+006F U+0072 U+0067
'    Restored: U+0061 U+002E U+006F U+0072 U+0067
'    
'    my_company.com --> my_company.com --> my_company.com
'    Original: U+006D U+0079 U+005F U+0063 U+006F U+006D U+0070 U+0061 U+006E U+0079 U+002E U+0063 U+006F U+006D
'    Restored: U+006D U+0079 U+005F U+0063 U+006F U+006D U+0070 U+0061 U+006E U+0079 U+002E U+0063 U+006F U+006D

Remarks

For more information about domain names, labels, and label separators, see the remarks for the IdnMapping.GetAscii(String, Int32, Int32) method.

Applies to

GetUnicode(String, Int32)

Decodes a substring of one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

public:
 System::String ^ GetUnicode(System::String ^ ascii, int index);
public string GetUnicode (string ascii, int index);
member this.GetUnicode : string * int -> string
Public Function GetUnicode (ascii As String, index As Integer) As String

Parameters

ascii
String

The string to decode, which consists of one or more labels in the US-ASCII character range (U+0020 to U+007E) encoded according to the IDNA standard.

index
Int32

A zero-based offset into ascii that specifies the start of the substring to decode. The decoding operation continues to the end of the ascii string.

Returns

The Unicode equivalent of the IDNA substring specified by the ascii and index parameters.

Exceptions

ascii is null.

index is less than zero.

-or-

index is greater than the length of ascii.

ascii is invalid based on the AllowUnassigned and UseStd3AsciiRules properties, and the IDNA standard.

Remarks

For more information about domain names, labels, and label separators, see the remarks for the IdnMapping.GetAscii(String, Int32, Int32) method.

Applies to

GetUnicode(String, Int32, Int32)

Decodes a substring of a specified length that contains one or more domain name labels, encoded according to the IDNA standard, to a string of Unicode characters.

public:
 System::String ^ GetUnicode(System::String ^ ascii, int index, int count);
public string GetUnicode (string ascii, int index, int count);
member this.GetUnicode : string * int * int -> string
Public Function GetUnicode (ascii As String, index As Integer, count As Integer) As String

Parameters

ascii
String

The string to decode, which consists of one or more labels in the US-ASCII character range (U+0020 to U+007E) encoded according to the IDNA standard.

index
Int32

A zero-based offset into ascii that specifies the start of the substring.

count
Int32

The number of characters to convert in the substring that starts at the position specified by index in the ascii string.

Returns

The Unicode equivalent of the IDNA substring specified by the ascii, index, and count parameters.

Exceptions

ascii is null.

index or count is less than zero.

-or-

index is greater than the length of ascii.

-or-

index is greater than the length of ascii minus count.

ascii is invalid based on the AllowUnassigned and UseStd3AsciiRules properties, and the IDNA standard.

Remarks

For more information about domain names, labels, and label separators, see the remarks for the IdnMapping.GetAscii(String, Int32, Int32) method.

Applies to