CaseInsensitiveComparer CaseInsensitiveComparer CaseInsensitiveComparer CaseInsensitiveComparer Class

定義

比較兩個物件是否相等,忽略字串的大小寫。Compares two objects for equivalence, ignoring the case of strings.

public ref class CaseInsensitiveComparer : System::Collections::IComparer
[System.Runtime.InteropServices.ComVisible(true)]
[System.Serializable]
public class CaseInsensitiveComparer : System.Collections.IComparer
type CaseInsensitiveComparer = class
    interface IComparer
Public Class CaseInsensitiveComparer
Implements IComparer
繼承
CaseInsensitiveComparerCaseInsensitiveComparerCaseInsensitiveComparerCaseInsensitiveComparer
屬性
實作

範例

下列程式碼範例會建立一個區分大小寫的雜湊表和不區分大小寫的雜湊表,並示範它們的行為差異,即使兩者都包含相同的項目。The following code example creates a case-sensitive hash table and a case-insensitive hash table and demonstrates the difference in their behavior, even if both contain the same elements.

using namespace System;
using namespace System::Collections;
using namespace System::Globalization;
int main()
{
   
   // Create a Hashtable using the default hash code provider and the default comparer.
   Hashtable^ myHT1 = gcnew Hashtable;
   myHT1->Add( "FIRST", "Hello" );
   myHT1->Add( "SECOND", "World" );
   myHT1->Add( "THIRD", "!" );
   
   // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
   // based on the culture of the current thread.
   Hashtable^ myHT2 = gcnew Hashtable( gcnew CaseInsensitiveHashCodeProvider,gcnew CaseInsensitiveComparer );
   myHT2->Add( "FIRST", "Hello" );
   myHT2->Add( "SECOND", "World" );
   myHT2->Add( "THIRD", "!" );
   
   // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
   // based on the InvariantCulture.
   Hashtable^ myHT3 = gcnew Hashtable( CaseInsensitiveHashCodeProvider::DefaultInvariant,CaseInsensitiveComparer::DefaultInvariant );
   myHT3->Add( "FIRST", "Hello" );
   myHT3->Add( "SECOND", "World" );
   myHT3->Add( "THIRD", "!" );
   
   // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
   // based on the Turkish culture (tr-TR), where "I" is not the uppercase version of "i".
   CultureInfo^ myCul = gcnew CultureInfo( "tr-TR" );
   Hashtable^ myHT4 = gcnew Hashtable( gcnew CaseInsensitiveHashCodeProvider( myCul ),gcnew CaseInsensitiveComparer( myCul ) );
   myHT4->Add( "FIRST", "Hello" );
   myHT4->Add( "SECOND", "World" );
   myHT4->Add( "THIRD", "!" );
   
   // Search for a key in each hashtable.
   Console::WriteLine( "first is in myHT1: {0}", myHT1->ContainsKey( "first" ) );
   Console::WriteLine( "first is in myHT2: {0}", myHT2->ContainsKey( "first" ) );
   Console::WriteLine( "first is in myHT3: {0}", myHT3->ContainsKey( "first" ) );
   Console::WriteLine( "first is in myHT4: {0}", myHT4->ContainsKey( "first" ) );
}

/* 
This code produces the following output.  Results vary depending on the system's culture settings.

first is in myHT1: False
first is in myHT2: True
first is in myHT3: True
first is in myHT4: False

*/
using System;
using System.Collections;
using System.Globalization;

public class SamplesHashtable  {

   public static void Main()  {

      // Create a Hashtable using the default hash code provider and the default comparer.
      Hashtable myHT1 = new Hashtable();
      myHT1.Add("FIRST", "Hello");
      myHT1.Add("SECOND", "World");
      myHT1.Add("THIRD", "!");

      // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      // based on the culture of the current thread.
      Hashtable myHT2 = new Hashtable( new CaseInsensitiveHashCodeProvider(), new CaseInsensitiveComparer() );
      myHT2.Add("FIRST", "Hello");
      myHT2.Add("SECOND", "World");
      myHT2.Add("THIRD", "!");

      // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      // based on the InvariantCulture.
      Hashtable myHT3 = new Hashtable( CaseInsensitiveHashCodeProvider.DefaultInvariant, CaseInsensitiveComparer.DefaultInvariant );
      myHT3.Add("FIRST", "Hello");
      myHT3.Add("SECOND", "World");
      myHT3.Add("THIRD", "!");

      // Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      // based on the Turkish culture (tr-TR), where "I" is not the uppercase version of "i".
      CultureInfo myCul = new CultureInfo( "tr-TR" );
      Hashtable myHT4 = new Hashtable( new CaseInsensitiveHashCodeProvider( myCul ), new CaseInsensitiveComparer( myCul ) );
      myHT4.Add("FIRST", "Hello");
      myHT4.Add("SECOND", "World");
      myHT4.Add("THIRD", "!");

      // Search for a key in each hashtable.
      Console.WriteLine( "first is in myHT1: {0}", myHT1.ContainsKey( "first" ) );
      Console.WriteLine( "first is in myHT2: {0}", myHT2.ContainsKey( "first" ) );
      Console.WriteLine( "first is in myHT3: {0}", myHT3.ContainsKey( "first" ) );
      Console.WriteLine( "first is in myHT4: {0}", myHT4.ContainsKey( "first" ) );

   }

}


/* 
This code produces the following output.  Results vary depending on the system's culture settings.

first is in myHT1: False
first is in myHT2: True
first is in myHT3: True
first is in myHT4: False

*/

Imports System
Imports System.Collections
Imports System.Globalization

Public Class SamplesHashtable

   Public Shared Sub Main()

      ' Create a Hashtable using the default hash code provider and the default comparer.
      Dim myHT1 As New Hashtable()
      myHT1.Add("FIRST", "Hello")
      myHT1.Add("SECOND", "World")
      myHT1.Add("THIRD", "!")

      ' Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      ' based on the culture of the current thread.
      Dim myHT2 As New Hashtable(New CaseInsensitiveHashCodeProvider(), New CaseInsensitiveComparer())
      myHT2.Add("FIRST", "Hello")
      myHT2.Add("SECOND", "World")
      myHT2.Add("THIRD", "!")

      ' Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      ' based on the InvariantCulture.
      Dim myHT3 As New Hashtable(CaseInsensitiveHashCodeProvider.DefaultInvariant, CaseInsensitiveComparer.DefaultInvariant)
      myHT3.Add("FIRST", "Hello")
      myHT3.Add("SECOND", "World")
      myHT3.Add("THIRD", "!")

      ' Create a Hashtable using a case-insensitive code provider and a case-insensitive comparer,
      ' based on the Turkish culture (tr-TR), where "I" is not the uppercase version of "i".
      Dim myCul As New CultureInfo("tr-TR")
      Dim myHT4 As New Hashtable(New CaseInsensitiveHashCodeProvider(myCul), New CaseInsensitiveComparer(myCul))
      myHT4.Add("FIRST", "Hello")
      myHT4.Add("SECOND", "World")
      myHT4.Add("THIRD", "!")

      ' Search for a key in each hashtable.
      Console.WriteLine("first is in myHT1: {0}", myHT1.ContainsKey("first"))
      Console.WriteLine("first is in myHT2: {0}", myHT2.ContainsKey("first"))
      Console.WriteLine("first is in myHT3: {0}", myHT3.ContainsKey("first"))
      Console.WriteLine("first is in myHT4: {0}", myHT4.ContainsKey("first"))

   End Sub 'Main 

End Class 'SamplesHashtable


'This code produces the following output.  Results vary depending on the system's culture settings.
'
'first is in myHT1: False
'first is in myHT2: True
'first is in myHT3: True
'first is in myHT4: False

備註

CaseInsensitiveComparer 會實作IComparer介面,支援在字串不區分大小寫比較,就如同CaseInsensitiveHashCodeProvider實作IHashCodeProvider支援不區分大小寫的比較,在字串上的介面。CaseInsensitiveComparer implements the IComparer interface supporting case-insensitive comparisons on strings, just as CaseInsensitiveHashCodeProvider implements the IHashCodeProvider interface supporting case-insensitive comparisons on strings.

重要

我們不建議您改用CaseInsensitiveComparer開發新的類別。We don't recommend that you use the CaseInsensitiveComparer class for new development. 相反地,我們建議您使用System.StringComparer所傳回的物件StringComparer.CurrentCultureIgnoreCaseStringComparer.InvariantCultureIgnoreCase,或StringComparer.OrdinalIgnoreCase屬性。Instead, we recommend that you use the System.StringComparer object returned by the StringComparer.CurrentCultureIgnoreCase, StringComparer.InvariantCultureIgnoreCase, or StringComparer.OrdinalIgnoreCase property.

Comparer類別是預設的實作IComparer介面,並執行區分大小寫的字串比較。The Comparer class is the default implementation of the IComparer interface and performs case-sensitive string comparisons.

做為索引鍵所使用的物件Hashtable才能覆寫Object.GetHashCode方法 (或IHashCodeProvider介面) 和Object.Equals方法 (或IComparer介面)。The objects used as keys by a Hashtable are required to override the Object.GetHashCode method (or the IHashCodeProvider interface) and the Object.Equals method (or the IComparer interface). 方法或介面的實作必須處理區分大小寫相同的方式;否則,Hashtable可能不正確地運作。The implementation of both methods or interfaces must handle case sensitivity the same way; otherwise, the Hashtable might behave incorrectly. 例如,建立Hashtable,您必須使用此類別CaseInsensitiveHashCodeProvider類別或任何不區分大小寫IHashCodeProvider實作。For example, when creating a Hashtable, you must use this class with the CaseInsensitiveHashCodeProvider class or any case-insensitive IHashCodeProvider implementation.

字串比較可能會有不同的結果,根據文化特性。String comparisons might have different results depending on the culture. 如需有關特定文化特性比較的詳細資訊,請參閱 < System.Globalization 命名空間並全球化和當地語系化For more information on culture-specific comparisons, see the System.Globalization namespace and Globalization and Localization.

建構函式

CaseInsensitiveComparer() CaseInsensitiveComparer() CaseInsensitiveComparer() CaseInsensitiveComparer()

使用目前執行緒的 CaseInsensitiveComparer,初始化 CurrentCulture 類別的新執行個體。Initializes a new instance of the CaseInsensitiveComparer class using the CurrentCulture of the current thread.

CaseInsensitiveComparer(CultureInfo) CaseInsensitiveComparer(CultureInfo) CaseInsensitiveComparer(CultureInfo) CaseInsensitiveComparer(CultureInfo)

使用指定的 CaseInsensitiveComparer,初始化 CultureInfo 類別的新執行個體。Initializes a new instance of the CaseInsensitiveComparer class using the specified CultureInfo.

屬性

Default Default Default Default

取得 CaseInsensitiveComparer 的執行個體,它與目前執行緒的 CurrentCulture 相關聯,而且永遠可以使用。Gets an instance of CaseInsensitiveComparer that is associated with the CurrentCulture of the current thread and that is always available.

DefaultInvariant DefaultInvariant DefaultInvariant DefaultInvariant

取得 CaseInsensitiveComparer 的執行個體,它與 InvariantCulture 相關聯,而且永遠可以使用。Gets an instance of CaseInsensitiveComparer that is associated with InvariantCulture and that is always available.

方法

Compare(Object, Object) Compare(Object, Object) Compare(Object, Object) Compare(Object, Object)

執行兩個相同型別物件的區分大小寫比較,並傳回表示是否某個物件小於、等於或大於另外一方的值。Performs a case-insensitive comparison of two objects of the same type and returns a value indicating whether one is less than, equal to, or greater than the other.

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

判斷指定的物件是否等於目前的物件。Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

做為預設雜湊函式。Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

取得目前執行個體的 TypeGets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

建立目前 Object 的淺層複本 (Shallow Copy)。Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

傳回代表目前物件的字串。Returns a string that represents the current object.

(Inherited from Object)

適用於

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