ASP PAGE STRUCTURE-DIRECTIVES(PAGE DIRECTIVE)

 The following is  the list of the important elements of an ASP.NET page:

1. Directives
2. Code declaration blocks
3. ASP.NET controls
4. Code render blocks
5. Server-side comments
6. Server-side include directives
7. Literal text and HTML tags

Directives

• A directive controls how an ASP.NET page is compiled. 
• The beginning of a directive is marked with the characters <%@ and the end of a directive is marked with the characters %>. 
• A directive can appear anywhere within a page. By convention, however, a directive typically appears at the top of an ASP.NET page.
• There are several types of directives that you can add to an ASP.NET page. Two of the most useful types are page and import directives.

Page Directives

• Page directive  is used to specify the default programming language for a page. 
• Page directives can also be used to enable tracing and debugging for a page.
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• To change the default programming language of an ASP.NET page from Visual Basic to C#, for example, you would use the following page directive:

<%@ Page Language="C#" %>

• The keyword Page in a page directive is optional. The following two directives are equivalent:

<%@ Page Language="C#" %>
<%@ Language="C#" %>
DEBUG DIRECTIVE:

• To enable run time error messages to be displayed on a page, use the Debug directive.
•  To display errors in  ASP.NET page, include the following directive:

<%@ Page Debug="True" %>

• When  this directive  is included in the page , if an error is encountered when processing the page, the error is displayed.