HttpReceiveRequestEntityBody 使用应注意的地方

如果EntityBody数据很大，调用此函数是不能完全接收全部数据的，我们不能简单的判断

 BYTE* pBuffer = new BYTE[4096];
   ZeroMemory(pBuffer, 4096);
    string entityData;
    DWORD dwReceived = 0;
    if((NO_ERROR == HttpReceiveRequestEntityBody(reqQueueHandle, requestId, 0, pBuffer, 4096, &dwReceived, NULL)) && dwReceived > 0) {
        entityData += pBuffer;
    }
    delete[] pBuffer;

　　

就认为已经接受了全部的数据，根据PlatformSDK的注释:

Remarks

To retrieve an entire entity body, an application is expected to call HttpReceiveRequestEntityBody, passing in new buffers, until the function returns ERROR_HANDLE_EOF. As long as a buffer full of entity-body data is copied successfully and there is still more entity-body data waiting to be retrieved, the function returns NO_ERROR.

我们应该这样做

BYTE* pBuffer = new BYTE[4096];
   ZeroMemory(pBuffer, 4096);
   string entityData;
   DWORD dwReceived = 0;
   while((ERROR_HANDLE_EOF != HttpReceiveRequestEntityBody(reqQueueHandle, requestId, 0, pBuffer, 4096, &dwReceived, NULL)) && (dwReceived > 0)) {
        entityData += pBuffer;
        ZeroMemory(pBuffer, 4096);
    }
    delete[] pBuffer;