Removes the entry with the specified key from the string dictionary.
Assembly: System (in System.dll)
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.
| Exception | Condition |
|---|---|
| ArgumentNullException | The key is |
| NotSupportedException | The StringDictionary is read-only. |
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.
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
*/
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.