DictionaryBase.OnRemove Method (Object, Object)

 

Performs additional custom processes before removing an element from the DictionaryBase instance.

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

abstract OnRemove : 
        key:Object *
        value:Object -> unit
override OnRemove : 
        key:Object *
        value:Object -> unit

Parameters

key
Type: System.Object

The key of the element to remove.

value
Type: System.Object

The value of the element to remove.

The default implementation of this method is intended to be overridden by a derived class to perform some action before the specified element is removed.

The On* methods are invoked only on the instance returned by the Dictionary property, but not on the instance returned by the InnerHashtable property.

The default implementation of this method is an O(1) operation.

Notes to Implementers:

This method allows implementers to define processes that must be performed before removing the element from the underlying System.Collections.Hashtable. By defining this method, implementers can add functionality to inherited methods without having to override all other methods.

OnRemove is invoked before the standard Remove behavior, whereas OnRemoveComplete is invoked after the standard Remove behavior.

For example, implementers can prevent removal of elements by always throwing an exception in OnRemove.

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
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