DictionaryBase.IDictionary.Contains Method (Object)

 

Determines whether the DictionaryBase contains a specific key.

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

private abstract Contains : 
        key:Object -> bool
private override Contains : 
        key:Object -> bool

Parameters

key
Type: System.Object

The key to locate in the DictionaryBase.

Return Value

Type: System.Boolean

true if the DictionaryBase contains an element with the specified key; otherwise, false.

Exception Condition
ArgumentNullException

key is null.

This method is an O(1) operation.

Starting with the .NET Framework 2.0, this method uses the collection’s objects’ Equals and CompareTo methods on key to determine whether item exists. In the earlier versions of the .NET Framework, this determination was made by using the Equals and CompareTo methods of the key parameter on the objects in the collection.

The following code example implements the DictionaryBase class and uses that implementation to create a dictionary of String keys and values that have a Length of 5 characters or less.

No code example is currently available or this language may not be supported.

Universal Windows Platform
Available since 10
.NET Framework
Available since 1.1
Return to top
Show: