NameValueCollection Klasse

Definition

public ref class NameValueCollection : System::Collections::Specialized::NameObjectCollectionBase

public class NameValueCollection : System.Collections.Specialized.NameObjectCollectionBase

[System.Serializable]
public class NameValueCollection : System.Collections.Specialized.NameObjectCollectionBase

type NameValueCollection = class
    inherit NameObjectCollectionBase

Public Class NameValueCollection
Inherits NameObjectCollectionBase

Vererbung

Object

NameObjectCollectionBase

NameValueCollection

Abgeleitet

System.Net.WebHeaderCollection

System.Web.HttpClientCertificate

Attribute

SerializableAttribute

Beispiele

#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;

void PrintKeysAndValues( NameValueCollection^ myCol );
void PrintKeysAndValues2( NameValueCollection^ myCol );

int main()
{
   // Creates and initializes a new NameValueCollection.
   NameValueCollection^ myCol = gcnew NameValueCollection;
   myCol->Add( "red", "rojo" );
   myCol->Add( "green", "verde" );
   myCol->Add( "blue", "azul" );
   myCol->Add( "red", "rouge" );

   // Displays the values in the NameValueCollection in two different ways.
   Console::WriteLine( "Displays the elements using the AllKeys property and the Item (indexer) property:" );
   PrintKeysAndValues( myCol );
   Console::WriteLine( "Displays the elements using GetKey and Get:" );
   PrintKeysAndValues2( myCol );

   // Gets a value either by index or by key.
   Console::WriteLine( "Index 1 contains the value {0}.", myCol[ 1 ] );
   Console::WriteLine( "Key \"red\" has the value {0}.", myCol[ "red" ] );
   Console::WriteLine();

   // Copies the values to a string array and displays the string array.
   array<String^>^myStrArr = gcnew array<String^>(myCol->Count);
   myCol->CopyTo( myStrArr, 0 );
   Console::WriteLine( "The string array contains:" );
   for each ( String^ s in myStrArr )
      Console::WriteLine( "   {0}", s );
   Console::WriteLine();

   // Searches for a key and deletes it.
   myCol->Remove( "green" );
   Console::WriteLine( "The collection contains the following elements after removing \"green\":" );
   PrintKeysAndValues( myCol );

   // Clears the entire collection.
   myCol->Clear();
   Console::WriteLine( "The collection contains the following elements after it is cleared:" );
   PrintKeysAndValues( myCol );
}

void PrintKeysAndValues( NameValueCollection^ myCol )
{
   Console::WriteLine( "   KEY        VALUE" );
   for each ( String^ s in myCol->AllKeys )
      Console::WriteLine( "   {0,-10} {1}", s, myCol[s] );
   Console::WriteLine();
}

void PrintKeysAndValues2( NameValueCollection^ myCol )
{
   Console::WriteLine( "   [INDEX] KEY        VALUE" );
   for ( int i = 0; i < myCol->Count; i++ )
      Console::WriteLine( "   [{0}]     {1,-10} {2}", i, myCol->GetKey( i ), myCol->Get( i ) );
   Console::WriteLine();
}

/*

This code produces the following output.

Displays the elements using the AllKeys property and the Item (indexer) property:
   KEY        VALUE
   red        rojo,rouge
   green      verde
   blue       azul

Displays the elements using GetKey and Get:
   [INDEX] KEY        VALUE
   [0]     red        rojo,rouge
   [1]     green      verde
   [2]     blue       azul

Index 1 contains the value verde.
Key "red" has the value rojo,rouge.

The string array contains:
   rojo,rouge
   verde
   azul

The collection contains the following elements after removing "green":
   KEY        VALUE
   red        rojo,rouge
   blue       azul

The collection contains the following elements after it is cleared:
   KEY        VALUE


*/

using System;
using System.Collections;
using System.Collections.Specialized;

public class SamplesNameValueCollection  {

   public static void Main()  {

      // Creates and initializes a new NameValueCollection.
      NameValueCollection myCol = new NameValueCollection();
      myCol.Add( "red", "rojo" );
      myCol.Add( "green", "verde" );
      myCol.Add( "blue", "azul" );
      myCol.Add( "red", "rouge" );

      // Displays the values in the NameValueCollection in two different ways.
      Console.WriteLine( "Displays the elements using the AllKeys property and the Item (indexer) property:" );
      PrintKeysAndValues( myCol );
      Console.WriteLine( "Displays the elements using GetKey and Get:" );
      PrintKeysAndValues2( myCol );

      // Gets a value either by index or by key.
      Console.WriteLine( "Index 1 contains the value {0}.", myCol[1] );
      Console.WriteLine( "Key \"red\" has the value {0}.", myCol["red"] );
      Console.WriteLine();

      // Copies the values to a string array and displays the string array.
      String[] myStrArr = new String[myCol.Count];
      myCol.CopyTo( myStrArr, 0 );
      Console.WriteLine( "The string array contains:" );
      foreach ( String s in myStrArr )
         Console.WriteLine( "   {0}", s );
      Console.WriteLine();

      // Searches for a key and deletes it.
      myCol.Remove( "green" );
      Console.WriteLine( "The collection contains the following elements after removing \"green\":" );
      PrintKeysAndValues( myCol );

      // Clears the entire collection.
      myCol.Clear();
      Console.WriteLine( "The collection contains the following elements after it is cleared:" );
      PrintKeysAndValues( myCol );
   }

   public static void PrintKeysAndValues( NameValueCollection myCol )  {
      Console.WriteLine( "   KEY        VALUE" );
      foreach ( String s in myCol.AllKeys )
         Console.WriteLine( "   {0,-10} {1}", s, myCol[s] );
      Console.WriteLine();
   }

   public static void PrintKeysAndValues2( NameValueCollection myCol )  {
      Console.WriteLine( "   [INDEX] KEY        VALUE" );
      for ( int i = 0; i < myCol.Count; i++ )
         Console.WriteLine( "   [{0}]     {1,-10} {2}", i, myCol.GetKey(i), myCol.Get(i) );
      Console.WriteLine();
   }
}

/*

This code produces the following output.

Displays the elements using the AllKeys property and the Item (indexer) property:
   KEY        VALUE
   red        rojo,rouge
   green      verde
   blue       azul

Displays the elements using GetKey and Get:
   [INDEX] KEY        VALUE
   [0]     red        rojo,rouge
   [1]     green      verde
   [2]     blue       azul

Index 1 contains the value verde.
Key "red" has the value rojo,rouge.

The string array contains:
   rojo,rouge
   verde
   azul

The collection contains the following elements after removing "green":
   KEY        VALUE
   red        rojo,rouge
   blue       azul

The collection contains the following elements after it is cleared:
   KEY        VALUE


*/

' The following code example demonstrates several of the properties and methods of ListDictionary.

Imports System.Collections
Imports System.Collections.Specialized


Public Class SamplesNameValueCollection

    Public Shared Sub Main()

        ' Creates and initializes a new NameValueCollection.
        Dim myCol As New NameValueCollection()
        myCol.Add("red", "rojo")
        myCol.Add("green", "verde")
        myCol.Add("blue", "azul")
        myCol.Add("red", "rouge")

        ' Displays the values in the NameValueCollection in two different ways.
        Console.WriteLine("Displays the elements using the AllKeys property and the Item (indexer) property:")
        PrintKeysAndValues(myCol)
        Console.WriteLine("Displays the elements using GetKey and Get:")
        PrintKeysAndValues2(myCol)

        ' Gets a value either by index or by key.
        Console.WriteLine("Index 1 contains the value {0}.", myCol(1))
        Console.WriteLine("Key ""red"" has the value {0}.", myCol("red"))
        Console.WriteLine()

        ' Copies the values to a string array and displays the string array.
        Dim myStrArr(myCol.Count) As String
        myCol.CopyTo(myStrArr, 0)
        Console.WriteLine("The string array contains:")
        Dim s As String
        For Each s In myStrArr
            Console.WriteLine("   {0}", s)
        Next s
        Console.WriteLine()

        ' Searches for a key and deletes it.
        myCol.Remove("green")
        Console.WriteLine("The collection contains the following elements after removing ""green"":")
        PrintKeysAndValues(myCol)

        ' Clears the entire collection.
        myCol.Clear()
        Console.WriteLine("The collection contains the following elements after it is cleared:")
        PrintKeysAndValues(myCol)

    End Sub

    Public Shared Sub PrintKeysAndValues(myCol As NameValueCollection)
        Console.WriteLine("   KEY        VALUE")
        Dim s As String
        For Each s In  myCol.AllKeys
            Console.WriteLine("   {0,-10} {1}", s, myCol(s))
        Next s
        Console.WriteLine()
    End Sub

    Public Shared Sub PrintKeysAndValues2(myCol As NameValueCollection)
        Console.WriteLine("   [INDEX] KEY        VALUE")
        Dim i As Integer
        For i = 0 To myCol.Count - 1
            Console.WriteLine("   [{0}]     {1,-10} {2}", i, myCol.GetKey(i), myCol.Get(i))
        Next i
        Console.WriteLine()
    End Sub

End Class


'This code produces the following output.
'
'Displays the elements using the AllKeys property and the Item (indexer) property:
'   KEY        VALUE
'   red        rojo,rouge
'   green      verde
'   blue       azul
'
'Displays the elements using GetKey and Get:
'   [INDEX] KEY        VALUE
'   [0]     red        rojo,rouge
'   [1]     green      verde
'   [2]     blue       azul
'
'Index 1 contains the value verde.
'Key "red" has the value rojo,rouge.
'
'The string array contains:
'   red
'   green
'   blue
'
'
'The collection contains the following elements after removing "green":
'   KEY        VALUE
'   red        rojo,rouge
'   blue       azul
'
'The collection contains the following elements after it is cleared:
'   KEY        VALUE
'
'

Hinweise

Diese Auflistung basiert auf der NameObjectCollectionBase-Klasse.This collection is based on the NameObjectCollectionBase class. Jedes Element der Auflistung ist ein Schlüssel-Wert-Paar.Each element of the collection is a key/value pair. Im Gegensatz zum NameObjectCollectionBasekann diese Klasse jedoch mehrere Zeichen folgen Werte unter einem einzelnen Schlüssel speichern.However, unlike the NameObjectCollectionBase, this class can store multiple string values under a single key.

Diese Klasse kann für Header, Abfrage Zeichenfolgen und Formulardaten verwendet werden.This class can be used for headers, query strings and form data.

Auflistungen dieses Typs behalten nicht die Reihenfolge der Elemente bei, und beim Auflisten der Auflistung ist keine bestimmte Reihenfolge garantiert.Collections of this type do not preserve the ordering of elements, and no particular ordering is guaranteed when enumerating the collection.

Die Kapazität einer NameValueCollection ist die Anzahl der Elemente, die die NameValueCollection enthalten kann.The capacity of a NameValueCollection is the number of elements the NameValueCollection can hold. Beim Hinzufügen von Elementen wird die Kapazität aufgrund der erneuten Zuordnung automatisch erhöht.As elements are added, its capacity is automatically increased as required through reallocation.

Der Hashcode-Anbieter gibt Hashcodes für Schlüssel in der NameValueCollectionaus.The hash code provider dispenses hash codes for keys in the NameValueCollection. Der standardmäßige Hashcode-Anbieter ist der CaseInsensitiveHashCodeProvider.The default hash code provider is the CaseInsensitiveHashCodeProvider.

Der Vergleich bestimmt, ob zwei Schlüssel gleich sind.The comparer determines whether two keys are equal. Der Standardcomparer ist eine CaseInsensitiveComparer, die die Konventionen der invarianten Kulturverwendet; Das heißt, bei Schlüssel vergleichen wird die Groß-/Kleinschreibung standardmäßig nicht beachtet.The default comparer is a CaseInsensitiveComparer that uses the conventions of the invariant culture; that is, key comparisons are case-insensitive by default. Um Schlüssel Vergleiche mit Berücksichtigung der Groß-und Kleinschreibung durchzuführen, müssen Sie den NameValueCollection.NameValueCollection(IEqualityComparer)-Konstruktor aufzurufen und den Wert StringComparer.CurrentCulture, StringComparer.InvariantCultureoder StringComparer.Ordinal als equalityComparer Argument angeben.To perform case-sensitive key comparisons, call the NameValueCollection.NameValueCollection(IEqualityComparer) constructor, and provide a value of StringComparer.CurrentCulture, StringComparer.InvariantCulture, or StringComparer.Ordinal as the equalityComparer argument. Weitere Informationen dazu, wie sich die Kultur auf Vergleiche und Sortierungen auswirkt, finden Sie unter durchführen Kultur unabhängiger Zeichen folgen Operationen.For more information about how culture affects comparisons and sorting, see Performing Culture-Insensitive String Operations.

null ist als Schlüssel oder als Wert zulässig.null is allowed as a key or as a value.

Konstruktoren

Eigenschaften

Methoden

Explizite Schnittstellenimplementierungen

Erweiterungsmethoden

Gilt für:

Threadsicherheit

Öffentliche statische (Shared in Visual Basic) Member dieses Typs sind Thread sicher.Public static (Shared in Visual Basic) members of this type are thread safe. Bei Instanzmembern ist die Threadsicherheit nicht gewährleistet.Any instance members are not guaranteed to be thread safe.

Diese Implementierung stellt keinen synchronisierten (Thread sicheren) Wrapper für eine NameValueCollectionbereit, aber abgeleitete Klassen können mithilfe der SyncRoot-Eigenschaft der NameObjectCollectionBase Klasse eigene synchronisierte Versionen der NameValueCollection erstellen.This implementation does not provide a synchronized (thread safe) wrapper for a NameValueCollection, but derived classes can create their own synchronized versions of the NameValueCollection using the SyncRoot property of the NameObjectCollectionBase class.

Das Auflisten durch eine Auflistung ist intrinsisch keine Thread sichere Prozedur.Enumerating through a collection is intrinsically not a thread safe procedure. Selbst wenn eine Auflistung synchronisiert wird, besteht die Möglichkeit, dass andere Threads sie ändern. Dies führt dazu, dass der Enumerator eine Ausnahme auslöst.Even when a collection is synchronized, other threads can still modify the collection, which causes the enumerator to throw an exception. Um während der Enumeration Threadsicherheit zu gewährleisten, können Sie entweder die Auflistung während der gesamten Enumeration sperren oder die Ausnahmen, die aus von anderen Threads stammenden Änderungen resultieren, abfangen.To guarantee thread safety during enumeration, you can either lock the collection during the entire enumeration or catch the exceptions resulting from changes made by other threads.

Siehe auch

• NameObjectCollectionBase
• Durchführen kulturunabhängiger ZeichenfolgenoperationenPerforming Culture-Insensitive String Operations