How to use HTTP POST in C++ with Wininet - c++

Question

I am sending values of two variables using POST to the PHP server. The C++ application using Wininet connects to the server side script, but instead of sending the data correctly, it just shows empty fields in the parameters send using POST.
#include <windows.h> #include <wininet.h> #include <stdio.h> #include <fstream> #include <cstring>
#pragma comment (lib, "Wininet.lib")
#define SIZE 128
int main() {
HINTERNET Initialize, Connection, File;
DWORD dwBytes;
static const char *postData = "name=Jack+Din&age=38";
LPSTR accept1[2] = { "Accept: */*", NULL };
const char * const frmdata = "name=Arun+Pushkar&age=38";
static const char *hdrs[] = { "Content-Type: application/x-www-form-urlencoded" };
static const char *accept[] = { "*/*", NULL };
char ch;
Initialize = InternetOpen(L"HTTPGET", INTERNET_OPEN_TYPE_PRECONFIG, NULL, NULL, 0);
if (!Initialize)
{
printf("Failed to open session\n");
exit(0);
}
Connection = InternetConnect(Initialize, L"192.168.1.10", INTERNET_DEFAULT_HTTP_PORT,
NULL, NULL, INTERNET_SERVICE_HTTP, 0, 0);
File = HttpOpenRequest(
Connection,
L"POST",
L"/trydata.php",
L"HTTP/1.0",
NULL,
NULL,
INTERNET_FLAG_NO_CACHE_WRITE,
0);
unsigned long dataLen = strlen((char*)frmdata)+1;
bool res = HttpSendRequest(
File, // file to which reply will come
(LPCWSTR)hdrs,
0,
(char*)frmdata, // post variables to be send
dataLen); // length of data send
if (res)
{
std::ofstream webSource;
webSource.open("a.html");
while (InternetReadFile(File, &ch, 1, &dwBytes))
{
if (dwBytes != 1)break;
webSource << ch;
}
webSource.close();
}
InternetCloseHandle(File);
InternetCloseHandle(Connection);
InternetCloseHandle(Initialize);
return 0;
}
The server side script is
<?php
$yourname = isset($_POST['name']) ? $_POST['name'] : 'no name';
$yourage = isset($_POST['age']) ? $_POST['age'] : 'no age';
echo "Hello".htmlspecialchars($yourname). "!";
echo "Your Age".htmlspecialchars($yourage). "!";
?>
When I run this C++ code I get the following in my a.html:
Hello no Name!Your Age no Age!

Answer 1

I would use ATL Server classes to do the same. Here is the example:
CAtlHttpClient client;
AtlNavigateData navData;
LPCSTR lpData = "data=toto";
navData.SetMethod(ATL_HTTP_METHOD_POST);
navData.SetPostData((BYTE*)lpData, lstrlenA(lpData), _T("application/x-www-form-urlencoded"));
client.Navigate(_T("mysite.net"), _T("myscript.php"), &navData);
const char* pszBody = (const char*)client.GetBody();