ListDictionary::Remove Method (Object^)

 

Removes the entry with the specified key from the ListDictionary.

Namespace:   System.Collections.Specialized
Assembly:  System (in System.dll)

public:
virtual void Remove(
	Object^ key
) sealed

Parameters

key
Type: System::Object^

The key of the entry to remove.

Exception Condition
ArgumentNullException

key is null.

If the ListDictionary does not contain an element with the specified key, the ListDictionary remains unchanged. No exception is thrown.

This method is an O(n) operation, where n is Count.

The following code example adds to and removes elements from a ListDictionary.

#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( "Plums" );
   Console::WriteLine( "The collection contains the following elements after removing \"Plums\":" );
   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 "Plums":
   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 it is cleared:
   KEY                       VALUE

*/

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
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