Aracılığıyla paylaş


ListDictionary.Add(Object, Object) Yöntem

Tanım

öğesine belirtilen anahtara ve değere ListDictionarysahip bir girdi ekler.

public:
 virtual void Add(System::Object ^ key, System::Object ^ value);
public void Add (object key, object value);
public void Add (object key, object? value);
abstract member Add : obj * obj -> unit
override this.Add : obj * obj -> unit
Public Sub Add (key As Object, value As Object)

Parametreler

key
Object

Eklenecek girişin anahtarı.

value
Object

Eklenecek girdinin değeri. Değer olabilir null.

Uygulamalar

Özel durumlar

key, null değeridir.

içinde aynı anahtara sahip bir giriş zaten var ListDictionary.

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

Durumu ile karma kod değeri arasında bağıntısı olmayan bir nesne genellikle anahtar olarak kullanılmamalıdır. Örneğin, Dize nesneleri anahtar olarak kullanmak için StringBuilder nesnelerinden daha iyidir.

Özelliğini, içinde bulunmayan ListDictionarybir anahtarın değerini ayarlayarak yeni öğeler eklemek için de kullanabilirsinizItem[]; örneğin, myCollection["myNonexistentKey"] = myValue. Ancak, belirtilen anahtar içinde ListDictionaryzaten varsa, özelliğini ayarlamak Item[] eski değerin üzerine yazar. Buna karşılık, Add yöntemi mevcut öğeleri değiştirmez.

Bu yöntem bir O(n) işlemidir; burada n olur Count.

Şunlara uygulanır

Ayrıca bkz.