System.Web Namespace   HttpCachePolicy Class

---

Appends the specified text to the Cache-Control HTTP header.

[ VB ]
Public Sub AppendCacheExtension ( _
   ByVal extension As String _
)

[ C# ]
public void AppendCacheExtension (
   string extension
);

[ C++ ]
public: void AppendCacheExtension (
   String* extension
);

[ JScript ]
public function AppendCacheExtension (
   extension : String
);

extension

The text to append to the Cache-Control header.

Exception Type	Condition
ArgumentNullException	Occurs when extension is a null reference ( Nothing in Visual Basic ).

If the browser does not recognize cache control directives or extensions, the browser must ignore the unrecognized terms. For more information, see the document RFC 2616: Hypertext Transfer Protocol - HTTP/1.1, available on the World Wide Web Consortium's site at http://www.w3c.org .

[ VB, C#, JScript ] In the following example, which illustrates the use of a chche-control extension supported by Internet Explorer, the server is indicating to the browser that the content will not change for one hour ( pre-check=3600 ) and instructs it to retrieve the content directly from the local cache. However, if the content is modified by the server and the page is requested by the user within a fifteen-minute ( post-check= 900 ) to one-hour period, the browser displays the information found in the local cache but also performs a background check and optional fetch of the new content on the server.

[ VB ]
Response.Cache.AppendCacheExtension ( "post-check=900,pre-check=3600" )

[ C# ]
Response.Cache.AppendCacheExtension ( "post-check=900,pre-check=3600" );

[ JScript ] 
Response.Cache.AppendCacheExtension ( "post-check=900,pre-check=3600" )

HttpCachePolicy Members   Caching ASP.NET Pages

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