IMetadataInfo：：GetMetaPath 方法

發行項
07/19/2023

擷取目前內容的組態路徑。

語法

virtual PCWSTR GetMetaPath(  
   VOID  
) const = 0;

參數

此方法不會採用任何參數。

傳回值

包含組態路徑的字串指標。

備註

方法 GetMetaPath 會擷取目前內容的組態路徑。例如，在執行 IIS 7 之伺服器上的預設網站要求通常會傳回 MACHINE/WEBROOT/APPHOST/Default 網站路徑。

範例

下列程式碼範例示範如何建立使用 IHttpCoNtext：：GetMetadata 方法擷取 IMetadataInfo 介面指標的 HTTP 模組。此課程模組會完成下列步驟：

GetMetaPath使用方法來擷取目前要求的組態路徑。
使用 IHttpServer：：GetConfigObject 方法來擷取 INativeConfigurationSystem 介面的指標。
將目前要求的組態路徑傳遞至 INativeConfigurationSystem：：GetConfigSection 方法。
擷取 IIS 記錄設定的 INativeConfigurationElement 介面。
使用 INativeConfigurationElement：：GetBooleanProperty 方法來擷取值，指出是否啟用目前要求內容的記錄。
將此資訊傳回至 Web 用戶端，然後結束。

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

// Create a pointer for the global server interface.
IHttpServer * g_pHttpServer = NULL;

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

        // Create an HRESULT to receive return values from methods.
        HRESULT hr;
        // Create a boolean variable for the configuration setting.
        BOOL fDoNotLog = FALSE;
        // Create pointers to configuration objects.
        INativeConfigurationSystem * pConfigSystem = NULL;
        INativeConfigurationElement * pConfigElement = NULL;

        // Retrieve a pointer to the IMetadataInfo interface.
        IMetadataInfo * pMetadataInfo = pHttpContext->GetMetadata();
        
        // Retrieve the configuration path.
        PCWSTR pwszConfigPath = pMetadataInfo->GetMetaPath();

        // Retrieve the configuration object.
        pConfigSystem = g_pHttpServer->GetConfigObject();

        // Test for an error.
        if (NULL != pConfigSystem)
        {        
            // Retrieve the HTTP logging configuration section.
            hr = pConfigSystem->GetConfigSection(
                L"system.webServer/httpLogging",
                pwszConfigPath,&pConfigElement,NULL,NULL);
        
            // Test for an error.
            if (SUCCEEDED(hr))
            {
                // Retrieve the log settings from the configuration section.
                hr = pConfigElement->GetBooleanProperty(
                    L"dontLog",&fDoNotLog,NULL);

                // Test for an error.
                if (SUCCEEDED(hr))
                {
                    // 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);
                            
                    // Allocate space for the configuration path.
                    PSTR pszConfigPath =
                        (PSTR) pHttpContext->AllocateRequestMemory(
                        (DWORD) wcslen(pwszConfigPath) + 1 );

                    // Test for an error.
                    if (NULL == pszConfigPath)
                    {
                        // 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(pszConfigPath,
                        pwszConfigPath,wcslen(pwszConfigPath));

                    // Return the configuration path.
                    WriteResponseMessage(pHttpContext,
                        "\nConfiguration path:\t",pszConfigPath);

                    // Return the configuration setting.
                    WriteResponseMessage(pHttpContext,"\nLogging enabled:\t",
                        (FALSE == fDoNotLog) ? "Yes" : "No");

                    // 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 );

    // Store the pointer for the global server interface.
    g_pHttpServer = pGlobalInfo;

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

您的模組必須匯出 RegisterModule 函式。您可以為專案建立模組定義 (.def) 檔案，或使用參數編譯模組 /EXPORT:RegisterModule 來匯出此函式。如需詳細資訊，請參閱逐步解說：使用機器碼建立 Request-Level HTTP 模組。

您可以選擇性地使用呼叫慣例編譯器代碼， __stdcall (/Gz) 而不是明確宣告每個函式的呼叫慣例。

規格需求

類型	描述
Client	- 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
伺服器	- 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
產品	- 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
標頭	Httpserv.h

另請參閱

IMetadataInfo 介面

共用方式為

IMetadataInfo：：GetMetaPath 方法

語法

參數

傳回值

備註

範例

規格需求

另請參閱

意見反應

其他資源