IHttpContext::NotifyCustomNotification Method

IIS 7.0

Raises a custom request-level notification.

virtual HRESULT NotifyCustomNotification(
   ICustomNotificationProvider* pCustomOutput,
   BOOL* pfCompletionExpected
) = 0;


A pointer to an ICustomNotificationProvider.


true if asynchronous completion is expected; otherwise, false.

An HRESULT. Possible values include, but are not limited to, those in the following table.




Indicates that the operation was successful.


Indicates that there is insufficient memory to perform the operation.

The NotifyCustomNotification method raises the custom notification that is specified by the ICustomNotificationProvider interface in the pCustomOutput parameter.

Your module must register for the RQ_CUSTOM_NOTIFICATION notification, and your module must contain a CHttpModule::OnCustomRequestNotification method to process the custom notification. To raise the custom notification, your module must first create the instance of your custom ICustomNotificationProvider interface and pass that interface to the NotifyCustomNotification method for the current request context.


The following code example demonstrates how to create an HTTP module that performs the following tasks:

  1. Registers for the RQ_BEGIN_REQUEST and RQ_CUSTOM_NOTIFICATION notifications.

  2. Creates a CHttpModule class that contains OnBeginRequest and OnCustomRequestNotification methods.

    1. The OnBeginRequest method writes to the Event Viewer an event that specifies the current notification. The method then creates an instance of an ICustomNotificationProvider interface and raises the custom notification by using the NotifyCustomNotification method.

    2. The OnCustomRequestNotification method uses the ICustomNotificationProvider::QueryNotificationType method to retrieve the unique identifier for the custom notification. If the unique identifier matches, the OnCustomRequestNotification method writes to the Event Viewer an event that specifies that the custom notification was raised.

  3. Removes the CHttpModule class from memory and then 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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