IHttpSite::GetSiteId Method

IIS 7.0

Retrieves the unique ID for the Web site.

virtual DWORD GetSiteId(
) const = 0;

This method takes no parameters.

A DWORD that contains the unique ID for the Web site.

The GetSiteId method lets you retrieve the unique numeric value that identifies the Web site that is processing the current request. Each site that a Web administrator creates on an IIS Web server is automatically assigned a number that differentiates the Web site from other Web sites on the same server.


This unique identifier is used for managing Web sites and for logging Web requests. For example, the default Web site on a server running IIS will be assigned the number 1, and by default all log files from Web activity for the default Web site will be stored in the %SystemRoot%\System32\Logfiles\W3SVC1 folder. Additional Web sites that are created will be assigned a unique numeric value that is generated algorithmically from the Web site's settings.


The following code example demonstrates how to use the GetSiteId method to create an HTTP module that retrieves an IHttpSite interface. The module uses GetSiteId to retrieve the unique identifier for the Web site. The module then returns the identifier for the Web site to a Web client and exits.

Your module must export the RegisterModule function. You can export this function by creating a module definition (.def) file for your project, or you can compile the module by using the /EXPORT:RegisterModule switch. For more information, see Walkthrough: Creating a Request-Level HTTP Module By Using Native Code.

You can optionally compile the code by using the __stdcall (/Gz) calling convention instead of explicitly declaring the calling convention for each function.





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