Send JSON data via HttpOpenRequest

Question

I'm not programming at C++, but i'm asking for someone who does, so i'm sorry if my question is simple or stupid.

I need a simple example of using HttpOpenRequest/HttpSendRequest objects in order to send JSON data to some web service/site.

Thank you

Answer 1

Here is a very bare bones example to send a JSON string to http://hostname/path/scriptname. You will have to add proper error checking, status code checking, etc as needed:

HINTERNET hInternet = InternetOpen(_T("MyApp"), INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);

HINTERNET hConnect = InternetConnect(hInternet, _T("hostname"), INTERNET_DEFAULT_HTTP_PORT, NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);

LPTSTR rgpszAcceptTypes[] = {_T("application/json"), NULL};
HINTERNET hRequest = HttpOpenRequest(hConnect, _T("POST"), _T("/path/scriptname"), NULL, NULL, rgpszAcceptTypes, 0, 0);

HttpAddRequestHeaders(hRequest, _T("Content-Type: application/json\r\n"), -1, HTTP_ADDREQ_FLAG_ADD);

char *JsonData = "..."; // your actual JSON data here
HttpSendRequest(hRequest, NULL, 0, JsonData, strlen(JsonData))

DWORD StatusCode = 0;
DWORD StatusCodeLen = sizeof(StatusCode);
HttpQueryInfo(hRequest, HTTP_QUERY_STATUS_CODE | HTTP_QUERY_FLAG_NUMBER, &StatusCode, &StatusCodeLen, NULL);

if (StatusCode == 200)
{
    // use InternetQueryDataAvailable() and InternetReadFile()
    // to read any response data as needed...
}

InternetCloseHandle(hRequest);
InternetCloseHandle(hConnect);
InternetCloseHandle(hInternet);