正常化

更新：2007 年 11 月

某些 Unicode 字符具有多种等效的二进制表示形式。这些表示形式由组合和/或复合 Unicode 字符集组成。如果一个字符存在多种表示形式，会使搜索、排序、匹配和其他操作变得复杂。

Unicode 标准定义了一个称作正常化的过程。对于字符的任何二进制等效表示形式，该过程都可以返回一个二进制表示形式。正常化可以使用几种算法，这些算法称作正常化形式，它们遵守不同的规则。目前，.NET Framework 支持 Unicode 正常化形式 C、D、KC 和 KD。

说明：
正常化为同一正常化形式的两个字符串，可以进行序号比较，即逐个字符进行二进制比较。

有关 .NET Framework 支持的正常化形式的更多信息，请参见 NormalizationForm。有关正常化、字符分解和等效的更多信息，请参见 Unicode home site（Unicode 主站点）上的 Unicode 标准附件 15“Unicode Normalization Forms”（Unicode 范式）。

将字符串正常化

应用程序应使用 String 对象的 String.Normalize 方法返回默认情况下正常化为正常化形式 C 的新字符串。或者，通过指定 NormalizationForm 值，应用程序可以使用 String 对象的 String.Normalize 方法返回特定正常化为正常化形式 C、D、KC 或 KD 的新字符串。

测试字符串是否正常化

应用程序可以使用 String 对象的 String.IsNormalized 方法来确定对象的字符串值是否已正常化为正常化形式 C。或者，通过指定特定 NormalizationForm 值，应用程序可以使用 String 对象的 String.IsNormalized 方法来确定对象的字符串值是否已特定正常化为正常化形式 C、D、KC 或 KD。

示例

下面的代码示例演示了 IsNormalized 和 Normalize 方法。该代码示例测试原始字符串是否采用四种正常化形式之一，采用每种正常化形式创建原始字符串的一个版本，测试每个正常化字符串是否采用预期的正常化形式，然后在每个正常化字符串中显示每个字符的十六进制码位。

' This example demonstrates the String.Normalize method
'                       and the String.IsNormalized method
Imports System
Imports System.Text
Imports Microsoft.VisualBasic

Class Sample
   Public Shared Sub Main()
      ' Character c; combining characters acute and cedilla; character 3/4
      Dim s1 = New [String](New Char() {ChrW(&H0063), ChrW(&H0301), ChrW(&H0327), ChrW(&H00BE)})
      Dim s2 As String = Nothing
      Dim divider = New [String]("-"c, 80)
      divider = [String].Concat(Environment.NewLine, divider, Environment.NewLine)

      Try
         Show("s1", s1)
         Console.WriteLine()
         Console.WriteLine("U+0063 = LATIN SMALL LETTER C")
         Console.WriteLine("U+0301 = COMBINING ACUTE ACCENT")
         Console.WriteLine("U+0327 = COMBINING CEDILLA")
         Console.WriteLine("U+00BE = VULGAR FRACTION THREE QUARTERS")

         Console.WriteLine(divider)

         Console.WriteLine("A1) Is s1 normalized to the default form (Form C)?: {0}", s1.IsNormalized())
         Console.WriteLine("A2) Is s1 normalized to Form C?:  {0}", s1.IsNormalized(NormalizationForm.FormC))
         Console.WriteLine("A3) Is s1 normalized to Form D?:  {0}", s1.IsNormalized(NormalizationForm.FormD))
         Console.WriteLine("A4) Is s1 normalized to Form KC?: {0}", s1.IsNormalized(NormalizationForm.FormKC))
         Console.WriteLine("A5) Is s1 normalized to Form KD?: {0}", s1.IsNormalized(NormalizationForm.FormKD))

         Console.WriteLine(divider)

         Console.WriteLine("Set string s2 to each normalized form of string s1.")
         Console.WriteLine()
         Console.WriteLine("U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE")
         Console.WriteLine("U+0033 = DIGIT THREE")
         Console.WriteLine("U+2044 = FRACTION SLASH")
         Console.WriteLine("U+0034 = DIGIT FOUR")
         Console.WriteLine(divider)

         s2 = s1.Normalize()
         Console.Write("B1) Is s2 normalized to the default form (Form C)?: ")
         Console.WriteLine(s2.IsNormalized())
         Show("s2", s2)
         Console.WriteLine()

         s2 = s1.Normalize(NormalizationForm.FormC)
         Console.Write("B2) Is s2 normalized to Form C?: ")
         Console.WriteLine(s2.IsNormalized(NormalizationForm.FormC))
         Show("s2", s2)
         Console.WriteLine()

         s2 = s1.Normalize(NormalizationForm.FormD)
         Console.Write("B3) Is s2 normalized to Form D?: ")
         Console.WriteLine(s2.IsNormalized(NormalizationForm.FormD))
         Show("s2", s2)
         Console.WriteLine()

         s2 = s1.Normalize(NormalizationForm.FormKC)
         Console.Write("B4) Is s2 normalized to Form KC?: ")
         Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKC))
         Show("s2", s2)
         Console.WriteLine()

         s2 = s1.Normalize(NormalizationForm.FormKD)
         Console.Write("B5) Is s2 normalized to Form KD?: ")
         Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKD))
         Show("s2", s2)
         Console.WriteLine()

      Catch e As Exception
         Console.WriteLine(e.Message)
      End Try
   End Sub 'Main

   Private Shared Sub Show(title As String, s As String)
      Console.Write("Characters in string {0} = ", title)
      Dim x As Char
      For Each x In  s.ToCharArray()
         Console.Write("{0:X4} ", AscW(x))
      Next x
      Console.WriteLine()
   End Sub 'Show
End Class 'Sample
'
'This example produces the following results:
'
'Characters in string s1 = 0063 0301 0327 00BE
'
'U+0063 = LATIN SMALL LETTER C
'U+0301 = COMBINING ACUTE ACCENT
'U+0327 = COMBINING CEDILLA
'U+00BE = VULGAR FRACTION THREE QUARTERS
'
'--------------------------------------------------------------------------------
'
'A1) Is s1 normalized to the default form (Form C)?: False
'A2) Is s1 normalized to Form C?:  False
'A3) Is s1 normalized to Form D?:  False
'A4) Is s1 normalized to Form KC?: False
'A5) Is s1 normalized to Form KD?: False
'
'--------------------------------------------------------------------------------
'
'Set string s2 to each normalized form of string s1.
'
'U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE
'U+0033 = DIGIT THREE
'U+2044 = FRACTION SLASH
'U+0034 = DIGIT FOUR
'
'--------------------------------------------------------------------------------
'
'B1) Is s2 normalized to the default form (Form C)?: True
'Characters in string s2 = 1E09 00BE
'
'B2) Is s2 normalized to Form C?: True
'Characters in string s2 = 1E09 00BE
'
'B3) Is s2 normalized to Form D?: True
'Characters in string s2 = 0063 0327 0301 00BE
'
'B4) Is s2 normalized to Form KC?: True
'Characters in string s2 = 1E09 0033 2044 0034
'
'B5) Is s2 normalized to Form KD?: True
'Characters in string s2 = 0063 0327 0301 0033 2044 0034
'

// This example demonstrates the String.Normalize method
//                       and the String.IsNormalized method

using System;
using System.Text;

class Sample 
{
    public static void Main() 
    {
// Character c; combining characters acute and cedilla; character 3/4
    string s1 = new String( new char[] {'\u0063', '\u0301', '\u0327', '\u00BE'});
    string s2 = null;
    string divider = new String('-', 80);
    divider = String.Concat(Environment.NewLine, divider, Environment.NewLine);

    try 
    {
    Show("s1", s1);
    Console.WriteLine();
    Console.WriteLine("U+0063 = LATIN SMALL LETTER C");
    Console.WriteLine("U+0301 = COMBINING ACUTE ACCENT");
    Console.WriteLine("U+0327 = COMBINING CEDILLA");
    Console.WriteLine("U+00BE = VULGAR FRACTION THREE QUARTERS");
    Console.WriteLine(divider);

    Console.WriteLine("A1) Is s1 normalized to the default form (Form C)?: {0}", 
                                 s1.IsNormalized());
    Console.WriteLine("A2) Is s1 normalized to Form C?:  {0}", 
                                 s1.IsNormalized(NormalizationForm.FormC));
    Console.WriteLine("A3) Is s1 normalized to Form D?:  {0}", 
                                 s1.IsNormalized(NormalizationForm.FormD));
    Console.WriteLine("A4) Is s1 normalized to Form KC?: {0}", 
                                 s1.IsNormalized(NormalizationForm.FormKC));
    Console.WriteLine("A5) Is s1 normalized to Form KD?: {0}", 
                                 s1.IsNormalized(NormalizationForm.FormKD));

    Console.WriteLine(divider);

    Console.WriteLine("Set string s2 to each normalized form of string s1.");
    Console.WriteLine();
    Console.WriteLine("U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE");
    Console.WriteLine("U+0033 = DIGIT THREE");
    Console.WriteLine("U+2044 = FRACTION SLASH");
    Console.WriteLine("U+0034 = DIGIT FOUR");
    Console.WriteLine(divider);

    s2 = s1.Normalize();
    Console.Write("B1) Is s2 normalized to the default form (Form C)?: ");
    Console.WriteLine(s2.IsNormalized());
    Show("s2", s2);
    Console.WriteLine();

    s2 = s1.Normalize(NormalizationForm.FormC);
    Console.Write("B2) Is s2 normalized to Form C?: ");
    Console.WriteLine(s2.IsNormalized(NormalizationForm.FormC));
    Show("s2", s2);
    Console.WriteLine();

    s2 = s1.Normalize(NormalizationForm.FormD);
    Console.Write("B3) Is s2 normalized to Form D?: ");
    Console.WriteLine(s2.IsNormalized(NormalizationForm.FormD));
    Show("s2", s2);
    Console.WriteLine();

    s2 = s1.Normalize(NormalizationForm.FormKC);
    Console.Write("B4) Is s2 normalized to Form KC?: ");
    Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKC));
    Show("s2", s2);
    Console.WriteLine();

    s2 = s1.Normalize(NormalizationForm.FormKD);
    Console.Write("B5) Is s2 normalized to Form KD?: ");
    Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKD));
    Show("s2", s2);
    Console.WriteLine();
    }

    catch (Exception e) 
        {
        Console.WriteLine(e.Message);
        }
    }

    private static void Show(string title, string s)
    {
    Console.Write("Characters in string {0} = ", title);
    foreach(short x in s.ToCharArray())
        {
        Console.Write("{0:X4} ", x);
        }
    Console.WriteLine();
    }
}
/*
This example produces the following results:

Characters in string s1 = 0063 0301 0327 00BE

U+0063 = LATIN SMALL LETTER C
U+0301 = COMBINING ACUTE ACCENT
U+0327 = COMBINING CEDILLA
U+00BE = VULGAR FRACTION THREE QUARTERS

--------------------------------------------------------------------------------

A1) Is s1 normalized to the default form (Form C)?: False
A2) Is s1 normalized to Form C?:  False
A3) Is s1 normalized to Form D?:  False
A4) Is s1 normalized to Form KC?: False
A5) Is s1 normalized to Form KD?: False

--------------------------------------------------------------------------------

Set string s2 to each normalized form of string s1.

U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE
U+0033 = DIGIT THREE
U+2044 = FRACTION SLASH
U+0034 = DIGIT FOUR

--------------------------------------------------------------------------------

B1) Is s2 normalized to the default form (Form C)?: True
Characters in string s2 = 1E09 00BE

B2) Is s2 normalized to Form C?: True
Characters in string s2 = 1E09 00BE

B3) Is s2 normalized to Form D?: True
Characters in string s2 = 0063 0327 0301 00BE

B4) Is s2 normalized to Form KC?: True
Characters in string s2 = 1E09 0033 2044 0034

B5) Is s2 normalized to Form KD?: True
Characters in string s2 = 0063 0327 0301 0033 2044 0034

*/

// This example demonstrates the String.Normalize method
//                       and the String.IsNormalized method
using namespace System;
using namespace System::Text;
void Show( String^ title, String^ s )
{
   Console::Write( "Characters in string {0} = ", title );
   System::Collections::IEnumerator^ myEnum = s->ToCharArray()->GetEnumerator();
   while ( myEnum->MoveNext() )
   {

      /*) * __try_cast < Char * > ( myEnum -> Current );*/
      int x;
      Console::Write( "{0:X4} ", x );
   }

   Console::WriteLine();
}

int main()
{

   // Character c; combining characters acute and cedilla; character 3/4
   array<Char>^temp0 = {L'c',L'\u0301',L'\u0327',L'\u00BE'};
   String^ s1 = gcnew String( temp0 );
   String^ s2 = nullptr;
   String^ divider = gcnew String( '-',80 );
   divider = String::Concat( Environment::NewLine, divider, Environment::NewLine );
   try
   {
      Show( "s1", s1 );
      Console::WriteLine();
      Console::WriteLine( "U+0063 = LATIN SMALL LETTER C" );
      Console::WriteLine( "U+0301 = COMBINING ACUTE ACCENT" );
      Console::WriteLine( "U+0327 = COMBINING CEDILLA" );
      Console::WriteLine( "U+00BE = VULGAR FRACTION THREE QUARTERS" );
      Console::WriteLine( divider );
      Console::WriteLine( "A1) Is s1 normalized to the default form (Form C)?: {0}", s1->IsNormalized() );
      Console::WriteLine( "A2) Is s1 normalized to Form C?:  {0}", s1->IsNormalized( NormalizationForm::FormC ) );
      Console::WriteLine( "A3) Is s1 normalized to Form D?:  {0}", s1->IsNormalized( NormalizationForm::FormD ) );
      Console::WriteLine( "A4) Is s1 normalized to Form KC?: {0}", s1->IsNormalized( NormalizationForm::FormKC ) );
      Console::WriteLine( "A5) Is s1 normalized to Form KD?: {0}", s1->IsNormalized( NormalizationForm::FormKD ) );
      Console::WriteLine( divider );
      Console::WriteLine( "Set string s2 to each normalized form of string s1." );
      Console::WriteLine();
      Console::WriteLine( "U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE" );
      Console::WriteLine( "U+0033 = DIGIT THREE" );
      Console::WriteLine( "U+2044 = FRACTION SLASH" );
      Console::WriteLine( "U+0034 = DIGIT FOUR" );
      Console::WriteLine( divider );
      s2 = s1->Normalize();
      Console::Write( "B1) Is s2 normalized to the default form (Form C)?: " );
      Console::WriteLine( s2->IsNormalized() );
      Show( "s2", s2 );
      Console::WriteLine();
      s2 = s1->Normalize( NormalizationForm::FormC );
      Console::Write( "B2) Is s2 normalized to Form C?: " );
      Console::WriteLine( s2->IsNormalized( NormalizationForm::FormC ) );
      Show( "s2", s2 );
      Console::WriteLine();
      s2 = s1->Normalize( NormalizationForm::FormD );
      Console::Write( "B3) Is s2 normalized to Form D?: " );
      Console::WriteLine( s2->IsNormalized( NormalizationForm::FormD ) );
      Show( "s2", s2 );
      Console::WriteLine();
      s2 = s1->Normalize( NormalizationForm::FormKC );
      Console::Write( "B4) Is s2 normalized to Form KC?: " );
      Console::WriteLine( s2->IsNormalized( NormalizationForm::FormKC ) );
      Show( "s2", s2 );
      Console::WriteLine();
      s2 = s1->Normalize( NormalizationForm::FormKD );
      Console::Write( "B5) Is s2 normalized to Form KD?: " );
      Console::WriteLine( s2->IsNormalized( NormalizationForm::FormKD ) );
      Show( "s2", s2 );
      Console::WriteLine();
   }
   catch ( Exception^ e ) 
   {
      Console::WriteLine( e->Message );
   }

}

/*
This example produces the following results:

Characters in string s1 = 0063 0301 0327 00BE

U+0063 = LATIN SMALL LETTER C
U+0301 = COMBINING ACUTE ACCENT
U+0327 = COMBINING CEDILLA
U+00BE = VULGAR FRACTION THREE QUARTERS

--------------------------------------------------------------------------------

A1) Is s1 normalized to the default form (Form C)?: False
A2) Is s1 normalized to Form C?:  False
A3) Is s1 normalized to Form D?:  False
A4) Is s1 normalized to Form KC?: False
A5) Is s1 normalized to Form KD?: False

--------------------------------------------------------------------------------

Set string s2 to each normalized form of string s1.

U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE
U+0033 = DIGIT THREE
U+2044 = FRACTION SLASH
U+0034 = DIGIT FOUR

--------------------------------------------------------------------------------

B1) Is s2 normalized to the default form (Form C)?: True
Characters in string s2 = 1E09 00BE

B2) Is s2 normalized to Form C?: True
Characters in string s2 = 1E09 00BE

B3) Is s2 normalized to Form D?: True
Characters in string s2 = 0063 0327 0301 00BE

B4) Is s2 normalized to Form KC?: True
Characters in string s2 = 1E09 0033 2044 0034

B5) Is s2 normalized to Form KD?: True
Characters in string s2 = 0063 0327 0301 0033 2044 0034

*/

// This example demonstrates the String.Normalize method
//                       and the String.IsNormalized method
import System.*;
import System.Text.*;

class Sample
{
    public static void main(String[] args)
    {
        // Character c; combining characters acute and cedilla; character 3/4
        String s1 = new String(new char[] { '\u0063', '\u0301', '\u0327', 
            '\u00BE' });
        String s2 = null;
        String divider = new String('-', 80);
        divider = String.Concat(Environment.get_NewLine(), divider, 
            Environment.get_NewLine());

        try {
            Show("s1", s1);
            Console.WriteLine();
            Console.WriteLine("U+0063 = LATIN SMALL LETTER C");
            Console.WriteLine("U+0301 = COMBINING ACUTE ACCENT");
            Console.WriteLine("U+0327 = COMBINING CEDILLA");
            Console.WriteLine("U+00BE = VULGAR FRACTION THREE QUARTERS");
            Console.WriteLine(divider);

            Console.WriteLine("A1) Is s1 normalized to the default form " 
                + "(Form C)?: {0}", System.Convert.ToString(s1.IsNormalized()));
            Console.WriteLine("A2) Is s1 normalized to Form C?:  {0}", 
                System.Convert.ToString(s1.
                IsNormalized(NormalizationForm.FormC)));
            Console.WriteLine("A3) Is s1 normalized to Form D?:  {0}", 
                System.Convert.ToString(s1.
                IsNormalized(NormalizationForm.FormD)));
            Console.WriteLine("A4) Is s1 normalized to Form KC?: {0}", 
                System.Convert.ToString(s1.
                IsNormalized(NormalizationForm.FormKC)));
            Console.WriteLine("A5) Is s1 normalized to Form KD?: {0}", 
                System.Convert.ToString(s1.
                IsNormalized(NormalizationForm.FormKD)));

            Console.WriteLine(divider);

            Console.WriteLine("Set string s2 to each normalized form of " 
                + "string s1.");
            Console.WriteLine();
            Console.WriteLine("U+1E09 = LATIN SMALL LETTER C WITH CEDILLA " 
                + "AND ACUTE");
            Console.WriteLine("U+0033 = DIGIT THREE");
            Console.WriteLine("U+2044 = FRACTION SLASH");
            Console.WriteLine("U+0034 = DIGIT FOUR");
            Console.WriteLine(divider);

            s2 = s1.Normalize();
            Console.Write("B1) Is s2 normalized to the default form " 
                + "(Form C)?: ");
            Console.WriteLine(s2.IsNormalized());
            Show("s2", s2);
            Console.WriteLine();

            s2 = s1.Normalize(NormalizationForm.FormC);
            Console.Write("B2) Is s2 normalized to Form C?: ");
            Console.WriteLine(s2.IsNormalized(NormalizationForm.FormC));
            Show("s2", s2);
            Console.WriteLine();

            s2 = s1.Normalize(NormalizationForm.FormD);
            Console.Write("B3) Is s2 normalized to Form D?: ");
            Console.WriteLine(s2.IsNormalized(NormalizationForm.FormD));
            Show("s2", s2);
            Console.WriteLine();

            s2 = s1.Normalize(NormalizationForm.FormKC);
            Console.Write("B4) Is s2 normalized to Form KC?: ");
            Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKC));
            Show("s2", s2);
            Console.WriteLine();

            s2 = s1.Normalize(NormalizationForm.FormKD);
            Console.Write("B5) Is s2 normalized to Form KD?: ");
            Console.WriteLine(s2.IsNormalized(NormalizationForm.FormKD));
            Show("s2", s2);
            Console.WriteLine();
        }
        catch (System.Exception e) {
            Console.WriteLine(e.get_Message());
        }
    } //main

    private static void Show(String title, String s)
    {
        Console.Write("Characters in string {0} = ", title);
        char myCharArray[] = s.ToCharArray();
        for (int iCtr = 0; iCtr < myCharArray.length; iCtr++) {
            char c = myCharArray[iCtr];
            Console.Write(((System.Int32)c).ToString("X4") + " ");
        }
        Console.WriteLine();
    } //Show
} //Sample
/*
This example produces the following results:

Characters in string s1 = 0063 0301 0327 00BE

U+0063 = LATIN SMALL LETTER C
U+0301 = COMBINING ACUTE ACCENT
U+0327 = COMBINING CEDILLA
U+00BE = VULGAR FRACTION THREE QUARTERS

--------------------------------------------------------------------------------

A1) Is s1 normalized to the default form (Form C)?: False
A2) Is s1 normalized to Form C?:  False
A3) Is s1 normalized to Form D?:  False
A4) Is s1 normalized to Form KC?: False
A5) Is s1 normalized to Form KD?: False

--------------------------------------------------------------------------------

Set string s2 to each normalized form of string s1.

U+1E09 = LATIN SMALL LETTER C WITH CEDILLA AND ACUTE
U+0033 = DIGIT THREE
U+2044 = FRACTION SLASH
U+0034 = DIGIT FOUR

--------------------------------------------------------------------------------

B1) Is s2 normalized to the default form (Form C)?: True
Characters in string s2 = 1E09 00BE

B2) Is s2 normalized to Form C?: True
Characters in string s2 = 1E09 00BE

B3) Is s2 normalized to Form D?: True
Characters in string s2 = 0063 0327 0301 00BE

B4) Is s2 normalized to Form KC?: True
Characters in string s2 = 1E09 0033 2044 0034

B5) Is s2 normalized to Form KD?: True
Characters in string s2 = 0063 0327 0301 0033 2044 0034

*/

请参见

概念

正常化和排序