ASP.NET page directives

The ASP.NET page framework supports the following directives.

@ Page	Defines page-specific attributes used by the ASP.NET page parser and compiler. Can be included only in .aspx files.
@ Control	Defines control-specific attributes used by the ASP.NET page parser and compiler. Can be included only in .ascx files (user controls).
@ Import	Explicitly imports a namespace into a page or user control.
@ Implements	Declaratively indicates that a page or user control implements a specified .NET Framework interface.
@ Register	Associates aliases with namespaces and class names, thereby allowing user controls and custom server controls to be rendered when included in a requested page or user control.
@ Assembly	Links an assembly to the current page during compilation, making all the assembly's classes and interfaces available for use on the page.
@ Master	Identifies an ASP.NET master page.
@ WebHandler	Identifies an ASP.NET IHttpHandler page.
@ PreviousPageType	Provides the means to get strong typing against the previous page as accessed through the PreviousPage property.
@ MasterType	Assigns a class name to the Master property of an ASP.NET page, so that the page can get strongly typed references to members of the master page.
@ OutputCache	Declaratively controls the output caching policies of a page or user control.
@ Reference	Declaratively links a page or user control to the current page or user control.

ASP.NET treats any directive block (<%@ %>) that does not contain an explicit directive name as an @ Page directive for a page, or an @ Control directive for a user control.