IScriptMapInfo::GetManagedType Method

Article
06/14/2022

Retrieves the managed type for a request handler.

Syntax

virtual PCWSTR GetManagedType(  
   DWORD* pcchManagedType = NULL  
) const = 0;

Parameters

pcchManagedType
A pointer to a DWORD buffer that receives the length, in characters, of the managed type.

Return Value

A pointer to a string that contains the managed type.

Remarks

The GetManagedType method retrieves the type attribute for a request handler that is located in the <handlers> section of the ApplicationHost.config file. This attribute contains a list of the .NET Framework namespaces for a request handler. For example, the "TraceHandler-Integrated" request handler has a type attribute of "System.Web.Handlers.TraceHandler" by default.

Example

The following code example demonstrates how to use the IHttpContext::GetScriptMap method to create an HTTP module that retrieves a pointer to an IScriptMapInfo interface. The example then uses the GetManagedType method to retrieve the managed namespace for the request handler that is processing the current request. The module returns the managed type to a Web client and then exits.

The IScriptMapInfo::GetManagedType method differs from the IHttpServer::GetManagedType method in that the IScriptMapInfo::GetManagedType method will retrieve only the type attribute for the IScriptMapInfo interface, whereas the IHttpServer::GetManagedType can retrieve the type attribute for any virtual path.

#define _WINSOCKAPI_
#include <windows.h>
#include <sal.h>
#include <httpserv.h>

// Create the module class.
class MyHttpModule : public CHttpModule
{
public:
    REQUEST_NOTIFICATION_STATUS
    OnPostMapRequestHandler(
        IN IHttpContext * pHttpContext,
        IN IHttpEventProvider * pProvider
    )
    {
        UNREFERENCED_PARAMETER( pProvider );

        // Retrieve the IScriptMapInfo interface.
        IScriptMapInfo * pScriptMapInfo = pHttpContext->GetScriptMap();

        // Create an HRESULT to receive return values from methods.
        HRESULT hr;

        // Test for an error.
        if (NULL != pScriptMapInfo)
        {
            // Create buffers to store the managed type.
            PCWSTR pwszManagedType;
            PSTR   pszManagedType;
            DWORD  cchManagedType = 0;

            // Retrieve the managed type.
            pwszManagedType = pScriptMapInfo->GetManagedType(&cchManagedType);

            // Test for an error.
            if (NULL != pwszManagedType)
            {
                // Clear the existing response.
                pHttpContext->GetResponse()->Clear();
                // Set the MIME type to plain text.
                pHttpContext->GetResponse()->SetHeader(
                    HttpHeaderContentType,"text/plain",
                    (USHORT)strlen("text/plain"),TRUE);

                // Test the length of the managed type.
                if (cchManagedType > 0)
                {
                    // Allocate space to store data.
                    pszManagedType =
                        (PSTR) pHttpContext->AllocateRequestMemory
                        (cchManagedType + 1);
                    // Test for an error.
                    if (NULL == pszManagedType)
                    {
                        // Set the error status.
                        hr = HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY);
                        pProvider->SetErrorStatus( hr );
                        // End additional processing.
                        return RQ_NOTIFICATION_FINISH_REQUEST;
                    }
                    // Convert the WCHAR string to a CHAR string.
                    wcstombs(pszManagedType,
                        pwszManagedType,cchManagedType);
                }

                // Return the managed type to the client.
                WriteResponseMessage(pHttpContext,"Managed type: ",
                    (cchManagedType>0) ? pszManagedType : "n/a");

                // End additional processing.
                return RQ_NOTIFICATION_FINISH_REQUEST;
            }
        }

        // Return processing to the pipeline.
        return RQ_NOTIFICATION_CONTINUE;
    }

private:

    // Create a utility method that inserts a name/value pair into the response.
    HRESULT WriteResponseMessage(
        IHttpContext * pHttpContext,
        PCSTR pszName,
        PCSTR pszValue
    )
    {
        // Create an HRESULT to receive return values from methods.
        HRESULT hr;
        
        // Create a data chunk.
        HTTP_DATA_CHUNK dataChunk;
        // Set the chunk to a chunk in memory.
        dataChunk.DataChunkType = HttpDataChunkFromMemory;
        // Buffer for bytes written of data chunk.
        DWORD cbSent;

        // Set the chunk to the first buffer.
        dataChunk.FromMemory.pBuffer =
            (PVOID) pszName;
        // Set the chunk size to the first buffer size.
        dataChunk.FromMemory.BufferLength =
            (USHORT) strlen(pszName);
        // Insert the data chunk into the response.
        hr = pHttpContext->GetResponse()->WriteEntityChunks(
            &dataChunk,1,FALSE,TRUE,&cbSent);
        // Test for an error.
        if (FAILED(hr))
        {
            // Return the error status.
            return hr;
        }

        // Set the chunk to the second buffer.
        dataChunk.FromMemory.pBuffer =
            (PVOID) pszValue;
        // Set the chunk size to the second buffer size.
        dataChunk.FromMemory.BufferLength =
            (USHORT) strlen(pszValue);
        // Insert the data chunk into the response.
        hr = pHttpContext->GetResponse()->WriteEntityChunks(
            &dataChunk,1,FALSE,TRUE,&cbSent);
        // Test for an error.
        if (FAILED(hr))
        {
            // Return the error status.
            return hr;
        }

        // Return a success status.
        return S_OK;
    }
};

// Create the module's class factory.
class MyHttpModuleFactory : public IHttpModuleFactory
{
public:
    HRESULT
    GetHttpModule(
        OUT CHttpModule ** ppModule, 
        IN IModuleAllocator * pAllocator
    )
    {
        UNREFERENCED_PARAMETER( pAllocator );

        // Create a new instance.
        MyHttpModule * pModule = new MyHttpModule;

        // Test for an error.
        if (!pModule)
        {
            // Return an error if the factory cannot create the instance.
            return HRESULT_FROM_WIN32( ERROR_NOT_ENOUGH_MEMORY );
        }
        else
        {
            // Return a pointer to the module.
            *ppModule = pModule;
            pModule = NULL;
            // Return a success status.
            return S_OK;
        }            
    }

    void Terminate()
    {
        // Remove the class from memory.
        delete this;
    }
};

// Create the module's exported registration function.
HRESULT
__stdcall
RegisterModule(
    DWORD dwServerVersion,
    IHttpModuleRegistrationInfo * pModuleInfo,
    IHttpServer * pGlobalInfo
)
{
    UNREFERENCED_PARAMETER( dwServerVersion );
    UNREFERENCED_PARAMETER( pGlobalInfo );

    // Set the request notifications and exit.
    return pModuleInfo->SetRequestNotifications(
        new MyHttpModuleFactory,
        0,
        RQ_MAP_REQUEST_HANDLER
    );
}

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.

Requirements

Type	Description
Client	- IIS 7.0 on Windows Vista - IIS 7.5 on Windows 7 - IIS 8.0 on Windows 8 - IIS 10.0 on Windows 10
Server	- IIS 7.0 on Windows Server 2008 - IIS 7.5 on Windows Server 2008 R2 - IIS 8.0 on Windows Server 2012 - IIS 8.5 on Windows Server 2012 R2 - IIS 10.0 on Windows Server 2016
Product	- IIS 7.0, IIS 7.5, IIS 8.0, IIS 8.5, IIS 10.0 - IIS Express 7.5, IIS Express 8.0, IIS Express 10.0
Header	Httpserv.h