Hashtable.Contains Method (Object)


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Determines whether the Hashtable contains a specific key.

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

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


Type: System.Object

The key to locate in the Hashtable.

Return Value

Type: System.Boolean

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

Exception Condition

key is null.

Contains implements IDictionary.Contains. It behaves exactly as ContainsKey.

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 item 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 item parameter on the objects in the collection.

The following example shows how to determine whether the Hashtable contains a specific element.

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
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