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.NET Framework Class Library
StringDictionary..::.Remove Method

Removes the entry with the specified key from the string dictionary.

Namespace: System.Collections.Specialized
Assembly: System (in System.dll)
Syntax
Public Overridable Sub Remove ( _
	key As String _
)
public virtual void Remove(
	string key
)
public:
virtual void Remove(
	String^ key
)
abstract Remove : 
        key:string -> unit 
override Remove : 
        key:string -> unit 

Parameters

key
Type: System..::.String
The key of the entry to remove.
Exceptions
ExceptionCondition
ArgumentNullException

The key is nullNothingnullptra null reference (Nothing in Visual Basic).

NotSupportedException

The StringDictionary is read-only.

Remarks

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

The key is handled in a case-insensitive manner; it is translated to lowercase before it is used to find the entry to remove from the string dictionary.

This method is an O(1) operation.

Examples

The following code example demonstrates how to add and remove elements from a StringDictionary.


Imports System
Imports System.Collections
Imports System.Collections.Specialized

Public Class SamplesStringDictionary   

   Public Shared Sub Main()

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

      ' Displays the values in the StringDictionary.
      Console.WriteLine("Initial contents of the StringDictionary:")
      PrintKeysAndValues(myCol)

      ' Deletes an element.
      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 'Main

   Public Shared Sub PrintKeysAndValues(myCol As StringDictionary)
      Dim de As DictionaryEntry

      Console.WriteLine("   KEY        VALUE")
      For Each de In  myCol
         Console.WriteLine("   {0,-10} {1}", de.Key, de.Value)
      Next de
      Console.WriteLine()

   End Sub 'PrintKeysAndValues

End Class 'SamplesStringDictionary 


'This code produces the following output.
'
'Initial contents of the StringDictionary:
'   KEY        VALUE
'   green      verde
'   red        rojo
'   blue       azul
'
'The collection contains the following elements after removing "green":
'   KEY        VALUE
'   red        rojo
'   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 SamplesStringDictionary  {

   public static void Main()  {

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

      // Displays the values in the StringDictionary.
      Console.WriteLine( "Initial contents of the StringDictionary:" );
      PrintKeysAndValues( myCol );

      // Deletes an element.
      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( StringDictionary myCol )  {
      Console.WriteLine( "   KEY        VALUE" );
      foreach ( DictionaryEntry de in myCol )
         Console.WriteLine( "   {0,-10} {1}", de.Key, de.Value );
      Console.WriteLine();
   }

}

/*
This code produces the following output.

Initial contents of the StringDictionary:
   KEY        VALUE
   green      verde
   red        rojo
   blue       azul

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

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

*/


#using <System.dll>

using namespace System;
using namespace System::Collections;
using namespace System::Collections::Specialized;
void PrintKeysAndValues( StringDictionary^ myCol )
{
   Console::WriteLine( "   KEY        VALUE" );
   IEnumerator^ enum0 = myCol->GetEnumerator();
   while ( enum0->MoveNext() )
   {
      DictionaryEntry^ de = safe_cast<DictionaryEntry^>(enum0->Current);
      Console::WriteLine( "   {0,-10} {1}", de->Key, de->Value );
   }

   Console::WriteLine();
}

int main()
{

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

   // Displays the values in the StringDictionary.
   Console::WriteLine( "Initial contents of the StringDictionary:" );
   PrintKeysAndValues( myCol );

   // Deletes an element.
   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 );
}

/*
This code produces the following output.

Initial contents of the StringDictionary:
   KEY        VALUE
   green      verde
   red        rojo
   blue       azul

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

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

*/

Version Information

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1
Platforms

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.