Copyright © tutorialspoint.com
ASP.Net directives are instructions to specify optional settings, such as registering a custom control and page language. These settings describe how the web forms (.aspx) or user controls (.ascx) pages are processed by the .Net framework.
The syntax for declaring a directive is:
<%@ directive_name attribute=value [attribute=value] %>
In this section, we will just introduce the ASP.Net directives and we will use most of these directives throughout the tutorials.
The Application directive defines application-specific attributes. It is provided at the top of the global.aspx file.
The basic syntax for a sample Application directive is:
<%@ Application Language="C#" %>
The attributes of the Application directive are:
|Inherits||the name of the class from which to inherit|
|Description||text description of the application. Parsers and compilers ignore this|
|Language||language used in code blocks|
The Assembly directive links an assembly to the page or the application at parse time. This could appear either in the global.asax file for application-wide linking or in the page file or a user control file for linking to a page or user control.
The basic syntax for a sample Assembly directive is:
<%@ Assembly Name ="myassembly" %>
The attributes of the Assembly directive are:
|Name||the name of the assembly to be linked|
|Src||the path to the source file to be linked and compiled dynamically|
The Control directive is used with the user controls and appears in the user control (.ascx) files.
The basic syntax for a sample Control directive is:
<%@ Control Language="C#" EnableViewState="false" %>
The attributes of the Control directive are:
|AutoEventWireup||the Boolean value that enables or disables automatic association of events to handlers|
|ClassName||file name for the control|
|Debug||the Boolean value that enables or disables compiling with debug symbols|
|Description||text description of the control page, ignored by compiler|
|EnableViewState||the Boolean value that indicates whether view state is maintained across page requests|
|Explicit||for VB language, tells the compiler to use Option Explicit mode|
|Inherits||the class from which the control page inherits|
|Language||language for code and script|
|Src||the filename for the code-behind class|
|Strict||for VB language, tells the compiler to use the Option Strict mode|
The Implement directive indicates that the web page, master page or user control page must implement the specified .Net framework interface.
The basic syntax for an Implements directive is:
<%@ Implements Interface="interface_name" %>
The Import directive imports a namespace into a web page, user control pate of application. If the Import directive is specified in the global.asax, then it will apply to the entire application. If it is in a page of user control page, then it would apply to that page or control.
The basic syntax for an Import directive is:
<%@ namespace="System.Drawing" %>
The Master directive specifies a page file as being the mater page.
The basic syntax for a sample MasterPage directive is:
<%@ MasterPage Language="C#" AutoEventWireup="true" CodeFile="SiteMater.master.cs" Inherits="SiteMaster" %>
The MasterType directive assigns a class name to the Master property of a page, to make it strongly typed.
The basic syntax for a MasterType directive is:
<%@ MasterType attribute="value"[attribute="value" ...] %>
The OutputCache directive controls the output caching policies of a web page or a user control. We will discuss this directive in details, in data caching.
The basic syntax for a OutputCache directive is:
<%@ OutputCache Duration="15" VaryByParam="None" %>
The Page directive defines the attributes specific to the page file for the page parser and the compiler.
The basic syntax for a Page directive is:
<%@ Page Language="C#" AutoEventWireup="true" CodeFile="Default.aspx.cs" Inherits="_Default" Trace="true" %>
The attributes of the Page directive are:
|AutoEventWireup||the Boolean value that enables or disables Page events that are being automatically bound to methods; for example, Page_Load|
|Buffer||the Boolean value that enables or disables HTTP response buffering|
|ClassName||class name for the page|
|ClientTarget||the browser for which server controls should render content|
|CodeFile||name of the code behind file|
|Debug||the Boolean value that enables or disables compilation with debug symbols|
|Description||text description of the page, ignored by the parser|
|EnableSessionState||enables, disables or makes session state read-only|
|EnableViewState||the Boolean value that enables or disables view state across page requests|
|ErrorPage||URL for redirection if an unhandled page exception occurs|
|Inherits||the name of the code behind or other class|
|Language||programming language for code|
|Src||file name of the code behind class|
|Trace||enables or disables tracing|
|TraceMode||indicates how trace messages are to be displayed - sorted by time or category|
|Transaction||indicates if transactions are supported|
|ValidateRequest||the Boolean value that indicates whether all input data is validated against a hardcoded list of values|
The PreviousPageType directive assigns a class to a page, so that the page is strongly typed.
The basic syntax for a sample PreviousPagetype directive is:
<%@ PreviousPageType attribute="value"[attribute="value" ...] %>
The Reference directive indicates that another page or user control should be compiled and linked to the current page.
The basic syntax for a sample Reference directive is:
<%@ Reference Page ="somepage.aspx" %>
The Register derivative is used for registering the custom server controls and user controls.
The basic syntax for a sample Register directive is:
<%@ Register Src="~/footer.ascx" TagName="footer" TagPrefix="Tfooter" %>
Copyright © tutorialspoint.com