ListDictionary.Clear Yöntem

Tanım

Ad Alanı:

System.Collections.Specialized

Bütünleştirilmiş Kod:

System.Collections.Specialized.dll

Kaynak:

ListDictionary.cs

öğesinden ListDictionarytüm girdileri kaldırır.

public:
 virtual void Clear();

public void Clear ();

abstract member Clear : unit -> unit
override this.Clear : unit -> unit

Public Sub Clear ()

Uygulamalar

Clear()

Örnekler

Aşağıdaki kod örneği öğesine öğesini ekler ve öğesinden ListDictionaryöğe kaldırır.

#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
void PrintKeysAndValues( IDictionary^ myCol )
{
   Console::WriteLine( "   KEY                       VALUE" );
   IEnumerator^ myEnum = myCol->GetEnumerator();
   while ( myEnum->MoveNext() )
   {
      DictionaryEntry de = safe_cast<DictionaryEntry>(myEnum->Current);
      Console::WriteLine( "   {0,-25} {1}", de.Key, de.Value );
   }

   Console::WriteLine();
}

int main()
{
   
   // Creates and initializes a new ListDictionary.
   ListDictionary^ myCol = gcnew ListDictionary;
   myCol->Add( "Braeburn Apples", "1.49" );
   myCol->Add( "Fuji Apples", "1.29" );
   myCol->Add( "Gala Apples", "1.49" );
   myCol->Add( "Golden Delicious Apples", "1.29" );
   myCol->Add( "Granny Smith Apples", "0.89" );
   myCol->Add( "Red Delicious Apples", "0.99" );
   
   // Displays the values in the ListDictionary in three different ways.
   Console::WriteLine( "Initial contents of the ListDictionary:" );
   PrintKeysAndValues( myCol );
   
   // Deletes a key.
   myCol->Remove( "Gala Apples" );
   Console::WriteLine( "The collection contains the following elements after removing \"Gala Apples\":" );
   PrintKeysAndValues( myCol );
   
   // Clears the entire collection.
   myCol->Clear();
   Console::WriteLine( "The collection contains the following elements after it is cleared:" );
   PrintKeysAndValues( myCol );
}

/*
This code produces the following output.

Initial contents of the ListDictionary:
   KEY                       VALUE
   Braeburn Apples           1.49
   Fuji Apples               1.29
   Gala Apples               1.49
   Golden Delicious Apples   1.29
   Granny Smith Apples       0.89
   Red Delicious Apples      0.99

The collection contains the following elements after removing "Gala Apples":
   KEY                       VALUE
   Braeburn Apples           1.49
   Fuji Apples               1.29
   Golden Delicious Apples   1.29
   Granny Smith Apples       0.89
   Red Delicious Apples      0.99

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

*/

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

public class SamplesListDictionary  {

   public static void Main()  {

      // Creates and initializes a new ListDictionary.
      ListDictionary myCol = new ListDictionary();
      myCol.Add( "Braeburn Apples", "1.49" );
      myCol.Add( "Fuji Apples", "1.29" );
      myCol.Add( "Gala Apples", "1.49" );
      myCol.Add( "Golden Delicious Apples", "1.29" );
      myCol.Add( "Granny Smith Apples", "0.89" );
      myCol.Add( "Red Delicious Apples", "0.99" );

      // Displays the values in the ListDictionary in three different ways.
      Console.WriteLine( "Initial contents of the ListDictionary:" );
      PrintKeysAndValues( myCol );

      // Deletes a key.
      myCol.Remove( "Gala Apples" );
      Console.WriteLine( "The collection contains the following elements after removing \"Gala Apples\":" );
      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( IDictionary myCol )  {
      Console.WriteLine( "   KEY                       VALUE" );
      foreach ( DictionaryEntry de in myCol )
         Console.WriteLine( "   {0,-25} {1}", de.Key, de.Value );
      Console.WriteLine();
   }
}


/*
This code produces the following output.

Initial contents of the ListDictionary:
   KEY                       VALUE
   Braeburn Apples           1.49
   Fuji Apples               1.29
   Gala Apples               1.49
   Golden Delicious Apples   1.29
   Granny Smith Apples       0.89
   Red Delicious Apples      0.99

The collection contains the following elements after removing "Gala Apples":
   KEY                       VALUE
   Braeburn Apples           1.49
   Fuji Apples               1.29
   Golden Delicious Apples   1.29
   Granny Smith Apples       0.89
   Red Delicious Apples      0.99

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

*/

Imports System.Collections
Imports System.Collections.Specialized

Public Class SamplesListDictionary   

   Public Shared Sub Main()

      ' Creates and initializes a new ListDictionary.
      Dim myCol As New ListDictionary()
      myCol.Add("Braeburn Apples", "1.49")
      myCol.Add("Fuji Apples", "1.29")
      myCol.Add("Gala Apples", "1.49")
      myCol.Add("Golden Delicious Apples", "1.29")
      myCol.Add("Granny Smith Apples", "0.89")
      myCol.Add("Red Delicious Apples", "0.99")

      ' Displays the values in the ListDictionary in three different ways.
      Console.WriteLine("Initial contents of the ListDictionary:")
      PrintKeysAndValues(myCol)

      ' Deletes a key.
      myCol.Remove("Gala Apples")
      Console.WriteLine("The collection contains the following elements after removing ""Gala Apples"":")
      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 IDictionary)

      Console.WriteLine("   KEY                       VALUE")
      Dim de As DictionaryEntry
      For Each de In  myCol
         Console.WriteLine("   {0,-25} {1}", de.Key, de.Value)
      Next de
      Console.WriteLine()

   End Sub

End Class


'This code produces the following output.
'
'Initial contents of the ListDictionary:
'   KEY                       VALUE
'   Braeburn Apples           1.49
'   Fuji Apples               1.29
'   Gala Apples               1.49
'   Golden Delicious Apples   1.29
'   Granny Smith Apples       0.89
'   Red Delicious Apples      0.99
'
'The collection contains the following elements after removing "Gala Apples":
'   KEY                       VALUE
'   Braeburn Apples           1.49
'   Fuji Apples               1.29
'   Golden Delicious Apples   1.29
'   Granny Smith Apples       0.89
'   Red Delicious Apples      0.99
'
'The collection contains the following elements after it is cleared:
'   KEY                       VALUE
'

Açıklamalar

Count sıfır olarak ayarlanır ve koleksiyonun öğelerinden diğer nesnelere başvurular da serbest bırakılır.

Bu yöntem bir O(1) işlemidir.

Ayrıca bkz.

• Clear()