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OnChangedCallback Delegate

Defines a reference to a method that handles changes to monitored items.

Namespace:  System.Runtime.Caching
Assembly:  System.Runtime.Caching (in System.Runtime.Caching.dll)

public delegate void OnChangedCallback(
	Object state


Type: System.Object
The state of the dependent object that was changed.

The OnChangedCallback delegate is used by a change monitor to signal to a cache implementation that a change has occurred in an object whose contents are cached. The task of any implementation of the ChangeMonitor type is to monitor for changes in objects that are cached. For example, if the contents of a file are contained in a cache entry, and if the file is updated, its related cache entry must be changed also. In a typical cache implementation, a derived ChangeMonitor instance uses a OnChangedCallback delegate to notify the cache about a change.

.NET Framework

Supported in: 4

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

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