how to contruct HttpSendRequest method of WININET

Question

I have dummy web service with URI =http://localhost/IO_100_Service.svc/xml?id={id} which return data in XML format I want to call this service using WINInet APi in VC++.Can anybody help me how to use contruct "HttpSendRequest" method to add header and data to call this service .

Solution

Here is a sample code you should be able to modify to your needs. I tested it with VS2005 using command line template project.

    #include <tchar.h>
    #include <wininet.h>  

    /// ....

    HINTERNET hIntSession = 
      ::InternetOpen(_T("MyApp"), INTERNET_OPEN_TYPE_DIRECT, NULL, NULL, 0);

    HINTERNET hHttpSession = 
      InternetConnect(hIntSession, _T("api.twitter.com"), 80, 0, 0, INTERNET_SERVICE_HTTP, 0, NULL);

    HINTERNET hHttpRequest = HttpOpenRequest(
      hHttpSession, 
      _T("GET"), 
      _T("1/statuses/user_timeline.xml?screen_name=twitterapi"),
      0, 0, 0, INTERNET_FLAG_RELOAD, 0);

    TCHAR* szHeaders = _T("Content-Type: text/html\nMySpecialHeder: whatever");
    CHAR szReq[1024] = "";
    if( !HttpSendRequest(hHttpRequest, szHeaders, _tcslen(szHeaders), szReq, strlen(szReq))) {
      DWORD dwErr = GetLastError();
      /// handle error
    }

    CHAR szBuffer[1025];
    DWORD dwRead=0;
    while(::InternetReadFile(hHttpRequest, szBuffer, sizeof(szBuffer)-1, &dwRead) && dwRead) {
      szBuffer[dwRead] = 0;
      OutputDebugStringA(szBuffer);
      dwRead=0;
    }

    ::InternetCloseHandle(hHttpRequest);
    ::InternetCloseHandle(hHttpSession);
    ::InternetCloseHandle(hIntSession);