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Hashtable.Remove Method

Removes the element with the specified key from the Hashtable.

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

Public Overridable Sub Remove ( _
	key As Object _


Type: System.Object
The key of the element to remove.




key is Nothing.


The Hashtable is read-only.


The Hashtable has a fixed size.

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

This method is an O(1) operation.

The following example shows how to remove elements from the Hashtable.

Imports System
Imports System.Collections
Imports Microsoft.VisualBasic

Public Class SamplesHashtable    

    Public Shared Sub Main()

        ' Creates and initializes a new Hashtable.
        Dim myHT As New Hashtable()
        myHT.Add("1a", "The")
        myHT.Add("1b", "quick")
        myHT.Add("1c", "brown")
        myHT.Add("2a", "fox")
        myHT.Add("2b", "jumped")
        myHT.Add("2c", "over")
        myHT.Add("3a", "the")
        myHT.Add("3b", "lazy")
        myHT.Add("3c", "dog")

        ' Displays the Hashtable.
        Console.WriteLine("The Hashtable initially contains the following:")

        ' Removes the element with the key "3b".

        ' Displays the current state of the Hashtable.
        Console.WriteLine("After removing ""lazy"":")
    End Sub    

    Public Shared Sub PrintKeysAndValues(myHT As Hashtable)
        Dim de As DictionaryEntry
        For Each de In  myHT
            Console.WriteLine("    {0}:    {1}", de.Key, de.Value)
        Next de
    End Sub
End Class

' This code produces the following output.
'The Hashtable initially contains the following:
'    2c:    over
'    3a:    the
'    2b:    jumped
'    3b:    lazy
'    1b:    quick
'    3c:    dog
'    2a:    fox
'    1c:    brown
'    1a:    The
'After removing "lazy":
'    2c:    over
'    3a:    the
'    2b:    jumped
'    1b:    quick
'    3c:    dog
'    2a:    fox
'    1c:    brown
'    1a:    The

.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

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.