Appends the specified text to the Cache-Control HTTP header.
Assembly: System.Web (in System.Web.dll)
Public Sub AppendCacheExtension ( _ extension As String _ )
Dim instance As HttpCachePolicy Dim extension As String instance.AppendCacheExtension(extension)
public void AppendCacheExtension( string extension )
public: void AppendCacheExtension( String^ extension )
public function AppendCacheExtension( extension : String )
Parameters
- extension
- Type: System.String
The text to append to the Cache-Control header.
| Exception | Condition |
|---|---|
| ArgumentNullException |
extension is null. |
If the browser does not recognize cache control directives or extensions, the browser must ignore the unrecognized terms. For more information, see RFC 2616: Hypertext Transfer Protocol -- HTTP/1.1, available on the World Wide Web Consortium (W3C) Web site.
AppendCacheExtension is introduced in the .NET Framework version 3.5. For more information, see .NET Framework 3.5 Architecture.
The following code example demonstrates the use of a cache-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.
Response.Cache.AppendCacheExtension("post-check=900,pre-check=3600")
Response.Cache.AppendCacheExtension("post-check=900,pre-check=3600");
Response.Cache.AppendCacheExtension("post-check=900,pre-check=3600")
Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98
The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.