IHttpContext::MapHandler 方法

在网站上映射指定 URL 和 HTTP 谓词的处理程序。

语法

virtual HRESULT MapHandler(  
    DWORD               dwSiteId,  
    PCWSTR              pszSiteName,  
    PCWSTR              pszUrl,  
    PCSTR               pszVerb,  
    IScriptMapInfo **   ppScriptMap,  
    BOOL                fIgnoreWildcardMappings  
) = 0;  

parameters

dwSiteId
[IN]包含用于映射的 URL 的站点的 ID。

pszSiteName
[IN]指向包含目标 URL 的站点名称的字符串的指针。

pszUrl
[IN]指向包含用于映射的相对 URL 的字符串的指针。

pszVerb
[IN]指向包含用于映射的 HTTP 谓词的字符串的指针。

ppScriptMap
[OUT]指向 IScriptMapInfo 接口的指针,该接口包含所选脚本映射的详细信息。

fIgnoreWildcardMappings
[IN] true 如果忽略通配符映射,则为 ;否则为 false

返回值

HRESULT。 可能的值包括(但并不限于)下表中的项。

说明
S_OK 指示操作成功。
ERROR_NOT_ENOUGH_MEMORY 指示内存不足,无法执行操作。

备注

接口 IScriptMapInfoIHttpContext 接口的生存期内有效。

示例

下面的代码示例演示如何使用 MapHandler 方法创建返回 的 HTTP 模块。

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

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

        // Retrieve a pointer to the request.
        IHttpRequest * pHttpRequest = pHttpContext->GetRequest();

        // Test for an error.
        if (pHttpRequest != NULL)
        {
            // Length of the returned path.
            DWORD cbPhysicalPath = 0;
            
            // Get the length of the mapped path.
            pHttpContext->MapPath(L"/",NULL,&cbPhysicalPath);
            
            // Allocate space to store the path.
            PWSTR pwszPhysicalPath =
                (PWSTR) pHttpContext->AllocateRequestMemory(cbPhysicalPath+1);
            PSTR pszPhysicalPath  =
                (PSTR) pHttpContext->AllocateRequestMemory(cbPhysicalPath+1);
            
            // Test for an error.
            if ((pwszPhysicalPath==NULL) || (pszPhysicalPath==NULL))
            {
                // Set the error status.
                pHttpContext->GetResponse()->SetStatus(500,"Server Error",0,
                    HRESULT_FROM_WIN32(ERROR_NOT_ENOUGH_MEMORY));
                // End additional processing.
                return RQ_NOTIFICATION_FINISH_REQUEST;
            }
            
            // Retrieve the mapped path.
            pHttpContext->MapPath(L"/",pwszPhysicalPath,&cbPhysicalPath);
            
            // Convert the WCHAR string to a CHAR string.
            wcstombs_s((size_t*)&cbPhysicalPath,pszPhysicalPath,
                cbPhysicalPath,pwszPhysicalPath,cbPhysicalPath);
            
            // 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);

                // Return the path information.
            WriteResponseMessage(pHttpContext,
                "Path: ",pszPhysicalPath);

            // 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,
        RQ_BEGIN_REQUEST,
        0
    );
}

模块必须导出 RegisterModule 函数。 可以通过为项目创建模块定义 (.def) 文件导出此函数,也可以使用 开关编译模块 /EXPORT:RegisterModule 。 有关详细信息,请参阅 演练:使用本机代码创建Request-Level HTTP 模块

可以使用调用约定编译代码, __stdcall (/Gz) 而不是为每个函数显式声明调用约定。

要求

类型 说明
客户端 - Windows Vista 上的 IIS 7.0
- Windows 7 上的 IIS 7.5
- Windows 8 上的 IIS 8.0
- Windows 10 上的 IIS 10.0
服务器 - Windows Server 2008 上的 IIS 7.0
- Windows Server 2008 R2 上的 IIS 7.5
- Windows Server 2012 上的 IIS 8.0
- Windows Server 2012 R2 上的 IIS 8.5
- Windows Server 2016 上的 IIS 10.0
产品 - 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

另请参阅

IHttpContext 接口
IScriptMapInfo 接口