• Article

Dictionary<TKey, TValue>.Remove Method

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Removes the value with the specified key from the Dictionary<TKey, TValue>.

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

Syntax

'Declaration
Public Function Remove ( _
    key As TKey _
) As Boolean

public bool Remove(
    TKey key
)

Parameters

  • key
    Type: TKey
    The key of the element to remove.

Return Value

Type: System.Boolean
true if the element is successfully found and removed; otherwise, false. This method returns false if key is not found in the Dictionary<TKey, TValue>.

Implements

IDictionary<TKey, TValue>.Remove(TKey)

Exceptions

Exception Condition
ArgumentNullException

key is nulla null reference (Nothing in Visual Basic).

Remarks

If the Dictionary<TKey, TValue> does not contain an element with the specified key, the Dictionary<TKey, TValue> remains unchanged. No exception is thrown.

This method approaches an O(1) operation.

Examples

The following code example shows how to remove a key/value pair from a dictionary using the Remove method.

This code example is part of a larger example provided for the Dictionary<TKey, TValue> class.

' Use the Remove method to remove a key/value pair.
outputBlock.Text &= vbLf + "Remove(""doc"")" & vbCrLf
openWith.Remove("doc")

If Not openWith.ContainsKey("doc") Then
   outputBlock.Text &= "Key ""doc"" is not found." & vbCrLf
End If

// Use the Remove method to remove a key/value pair.
outputBlock.Text += "\nRemove(\"doc\")" + "\n";
openWith.Remove("doc");

if (!openWith.ContainsKey("doc"))
{
   outputBlock.Text += "Key \"doc\" is not found." + "\n";
}

Version Information

Silverlight

Supported in: 5, 4, 3

Silverlight for Windows Phone

Supported in: Windows Phone OS 7.1, Windows Phone OS 7.0

XNA Framework

Supported in: Xbox 360, Windows Phone OS 7.0

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.