CaseInsensitiveComparer.DefaultInvariant Propriedade
Definição
Importante
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Obtém uma instância da CaseInsensitiveComparer qual está associada InvariantCulture e que está sempre disponível.
public:
static property System::Collections::CaseInsensitiveComparer ^ DefaultInvariant { System::Collections::CaseInsensitiveComparer ^ get(); };
public static System.Collections.CaseInsensitiveComparer DefaultInvariant { get; }
static member DefaultInvariant : System.Collections.CaseInsensitiveComparer
Public Shared ReadOnly Property DefaultInvariant As CaseInsensitiveComparer
Valor da propriedade
Uma instância disso CaseInsensitiveComparer está associada InvariantCulturea .
Exemplos
O exemplo de código a seguir cria uma tabela de hash que diferencia maiúsculas de minúsculas e uma tabela de hash que não diferencia maiúsculas de minúsculas e demonstra a diferença em seu comportamento, mesmo que ambos contenham os mesmos elementos.
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
Comentários
Os procedimentos de comparação usam a CultureInfo.InvariantCulture ordem de classificação e as regras de casing. Comparações de cadeia de caracteres podem ter resultados diferentes dependendo da cultura. Para obter mais informações sobre comparações específicas à cultura, consulte o System.Globalization namespace e a globalização e a localização.