CaseInsensitiveComparer Classe

Définition

Compare deux objets pour contrôler leur équivalence, en ignorant la casse des chaînes.Compares two objects for equivalence, ignoring the case of strings.

public ref class CaseInsensitiveComparer : System::Collections::IComparer
public class CaseInsensitiveComparer : System.Collections.IComparer
[System.Serializable]
public 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
Héritage
CaseInsensitiveComparer
Attributs
Implémente

Exemples

L’exemple de code suivant crée une table de hachage respectant la casse et une table de hachage ne respectant pas la casse et montre la différence de comportement, même si les deux contiennent les mêmes éléments.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.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

End Class


'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

Remarques

CaseInsensitiveComparer implémente l’interface IComparer qui prend en charge les comparaisons ne respectant pas la casse sur les chaînes, tout comme CaseInsensitiveHashCodeProvider implémente l’interface IHashCodeProvider qui prend en charge les comparaisons ne respectant pas la casse sur les chaînes.CaseInsensitiveComparer implements the IComparer interface supporting case-insensitive comparisons on strings, just as CaseInsensitiveHashCodeProvider implements the IHashCodeProvider interface supporting case-insensitive comparisons on strings.

Important

Nous vous déconseillons d’utiliser la classe CaseInsensitiveComparer pour le nouveau développement.We don't recommend that you use the CaseInsensitiveComparer class for new development. Au lieu de cela, nous vous recommandons d’utiliser l’objet System.StringComparer retourné par la propriété StringComparer.CurrentCultureIgnoreCase, StringComparer.InvariantCultureIgnoreCaseou StringComparer.OrdinalIgnoreCase.Instead, we recommend that you use the System.StringComparer object returned by the StringComparer.CurrentCultureIgnoreCase, StringComparer.InvariantCultureIgnoreCase, or StringComparer.OrdinalIgnoreCase property.

La classe Comparer est l’implémentation par défaut de l’interface IComparer et effectue des comparaisons de chaînes respectant la casse.The Comparer class is the default implementation of the IComparer interface and performs case-sensitive string comparisons.

Les objets utilisés comme clés par un Hashtable sont requis pour substituer la méthode Object.GetHashCode (ou l’interface IHashCodeProvider) et la méthode Object.Equals (ou l’interface IComparer).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). L’implémentation des méthodes ou des interfaces doit gérer le respect de la casse de la même façon ; dans le cas contraire, le Hashtable peut se comporter de manière incorrecte.The implementation of both methods or interfaces must handle case sensitivity the same way; otherwise, the Hashtable might behave incorrectly. Par exemple, lors de la création d’un Hashtable, vous devez utiliser cette classe avec la classe CaseInsensitiveHashCodeProvider ou toute implémentation de IHashCodeProvider ne respectant pas la casse.For example, when creating a Hashtable, you must use this class with the CaseInsensitiveHashCodeProvider class or any case-insensitive IHashCodeProvider implementation.

Les comparaisons de chaînes peuvent avoir des résultats différents selon la culture.String comparisons might have different results depending on the culture. Pour plus d’informations sur les comparaisons spécifiques à la culture, consultez l’espace de noms System.Globalization et la globalisation et la localisation.For more information on culture-specific comparisons, see the System.Globalization namespace and Globalization and Localization.

Constructeurs

CaseInsensitiveComparer()

Initialise une nouvelle instance de la classe CaseInsensitiveComparer à l'aide de CurrentCulture du thread en cours.Initializes a new instance of the CaseInsensitiveComparer class using the CurrentCulture of the current thread.

CaseInsensitiveComparer(CultureInfo)

Initialise une nouvelle instance de la classe CaseInsensitiveComparer à l'aide du CultureInfo spécifié.Initializes a new instance of the CaseInsensitiveComparer class using the specified CultureInfo.

Propriétés

Default

Obtient une instance de CaseInsensitiveComparer associée au CurrentCulture du thread en cours et toujours disponible.Gets an instance of CaseInsensitiveComparer that is associated with the CurrentCulture of the current thread and that is always available.

DefaultInvariant

Obtient une instance de CaseInsensitiveComparer associée à InvariantCulture et toujours disponible.Gets an instance of CaseInsensitiveComparer that is associated with InvariantCulture and that is always available.

Méthodes

Compare(Object, Object)

Exécute une comparaison sans respect de la casse de deux objets du même type et retourne une valeur indiquant si l'un est inférieur, égal ou supérieur à l'autre.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)

Détermine si l'objet spécifié est identique à l'objet actuel.Determines whether the specified object is equal to the current object.

(Hérité de Object)
GetHashCode()

Fait office de fonction de hachage par défaut.Serves as the default hash function.

(Hérité de Object)
GetType()

Obtient le Type de l'instance actuelle.Gets the Type of the current instance.

(Hérité de Object)
MemberwiseClone()

Crée une copie superficielle du Object actuel.Creates a shallow copy of the current Object.

(Hérité de Object)
ToString()

Retourne une chaîne qui représente l'objet actuel.Returns a string that represents the current object.

(Hérité de Object)

S’applique à

Voir aussi