Updated: November 2007

This namespace includes the Cache class, a dictionary that enables you to store data objects such as hash tables and data sets. It also provides expiration functionality for those objects, and methods that enable you to add and remove the objects. You can add the objects to the cache with a dependency on other files or cache entries. In that case, the Cache object can invoke a callback method to notify your application when an object is removed from the cache.

 Classes

	Class	Description
	AggregateCacheDependency	Combines multiple dependencies between an item stored in an ASP.NET application's Cache object and an array of CacheDependency objects. This class cannot be inherited.
	Cache	Implements the cache for a Web application. This class cannot be inherited.
	CacheDependency	Establishes a dependency relationship between an item stored in an ASP.NET application's Cache object and a file, cache key, an array of either, or another CacheDependency object. The CacheDependency class monitors the dependency relationships so that when any of them changes, the cached item will be automatically removed.
	DatabaseNotEnabledForNotificationException	The exception that is thrown when a SQL Server database is not enabled to support dependencies associated with the SqlCacheDependency class. This class cannot be inherited.
	SqlCacheDependency	Establishes a relationship between an item stored in an ASP.NET application's Cache object and either a specific SQL Server database table or the results of a SQL Server 2005 query. This class cannot be inherited.
	SqlCacheDependencyAdmin	Performs administrative tasks required on a SQL Server database to support the SqlCacheDependency class when using polling-based dependencies. This class cannot be inherited.
	TableNotEnabledForNotificationException	The exception that is thrown when a SqlCacheDependency class is used against a database table that is not enabled for change notifications.

 Delegates

	Delegate	Description
	CacheItemRemovedCallback	Defines a callback method for notifying applications when a cached item is removed from the Cache.
	CacheItemUpdateCallback	Defines a callback method for notifying applications before a cached item is removed from the cache.

 Enumerations

	Enumeration	Description
	CacheItemPriority	Specifies the relative priority of items stored in the Cache object.
	CacheItemRemovedReason	Specifies the reason an item was removed from the Cache.
	CacheItemUpdateReason	Specifies the reason that a cached item is being removed from the Cache object.