Remove Method

Dictionary<TKey, TValue>.Remove Method

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

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

public bool Remove(
	TKey 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>.


IDictionary<TKey, TValue>.Remove(TKey)


key is null.

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.

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.

if (!openWith.ContainsKey("doc"))
    Console.WriteLine("Key \"doc\" is not found.");

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98, Windows CE, Windows Mobile for Smartphone, Windows Mobile for Pocket PC, Xbox 360, Zune

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

.NET Framework

Supported in: 3.5, 3.0, 2.0

.NET Compact Framework

Supported in: 3.5, 2.0

XNA Framework

Supported in: 3.0, 2.0, 1.0

Community Additions

© 2015 Microsoft