DictionaryBase.OnInsert Method (Object, Object)


Performs additional custom processes before inserting a new element into the DictionaryBase instance.

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

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


Type: System.Object

The key of the element to insert.

Type: System.Object

The value of the element to insert.

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

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 inserting the element into the underlying System.Collections.Hashtable. By defining this method, implementers can add functionality to inherited methods without having to override all other methods.

OnInsert is invoked before the standard Insert behavior, whereas OnInsertComplete is invoked after the standard Insert behavior.

For example, implementers can restrict which types of objects can be inserted into the System.Collections.Hashtable.

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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