Posting form using WinHttp

Do i need to add any headers before making a post to server?

For example, Currently I'm trying to send a request along with the post data this way,

  LPCWSTR post = L"name=User&subject=Hi&message=Hi";

    if (!(WinHttpSendRequest( hRequest, 
                            WINHTTP_NO_ADDITIONAL_HEADERS,
                            0, (LPVOID)post, wcslen(post), 
  开发者_C百科                          wcslen(post), 0)))
    {
          //error
    }

should this work?

What worked for me:

    LPSTR  post = "log=test";//in my php file: if(isset($_POST['log']))
    hRequest = WinHttpOpenRequest(hConnect,
                                    L"POST",
                                    L"/test.php",
                                    NULL,
                                    WINHTTP_NO_REFERER,
                                    WINHTTP_DEFAULT_ACCEPT_TYPES,
                                    0);
    bResults = WinHttpSendRequest(hRequest,
                                    L"content-type:application/x-www-form-urlencoded",
                                    -1,
                                    post,
                                    strlen(post),
                                    strlen(post),
                                    NULL);

I'd guess

• you need to pass narrow strings not wide as the post data. I don't know if you're specifying a content type for the posted data which would specify the encoding - you probably should if it's easy to - or just re-encode the string as UTF-8, or just assemble as a narrow string in the first place
• you might need an explicit end-of-line on the post data, i.e. add \r\n to your (narrow) string - I don't know if the API's going to add one since I assume you'd make the same call for binary data.

According to this MSDN page, it sure looks like your code sample will work, assuming you have are using the "POST" verb in WinHttpOpenRequest. If things just aren't working, then run Fiddler on both a web browser and your app, and compare headers generated from both cases.