使用cURL在外部网站上提交表单无效

Question

I am trying to retrieve information from an external website using cURL, but the website returns a blank page.

I took a close looker at the network functionality Chrome has and I think I found the problem, but I have no idea how to fix it. As seen in the image below, the server posts to a specific URL and then redirects to another one showing the final result.

This is the code I have right now:

$ch = curl_init();

curl_setopt($ch, CURLOPT_URL,"https://www.politie.nl/aangifte-of-melding-doen/controleer-handelspartij.html?_hn:type=action&_hn:ref=r199_r1_r1_r1");
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_POSTFIELDS,"url=&query=test");
curl_setopt($ch, CURLOPT_HTTPHEADER, array('Content-Type: application/x-www-form-urlencoded'));
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

echo curl_exec ($ch);

curl_close ($ch);

The website is in Dutch, but what I am trying to do is check a certain email, phone number or bank account number to see if they have been involved in any scams, so I would like to have the information that a user gets after submitting the form on the website.

The form is on this website: https://www.politie.nl/aangifte-of-melding-doen/controleer-handelspartij.html

I hope someone can help me and thank you for your time.

Answer 1

As was pointed out in one of the comments to your question, a redirect occurs after the form is submitted. But not only that - information transfer between the form submit request and the request after redirect happens through a session, with session id stored in a cookie, so in order to get the results you have to enable cookies, too.

// follow redirects
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, true);

// store and send cookies
$tmpfname = dirname(__FILE__).'/cookie.txt';
curl_setopt($ch, CURLOPT_COOKIEJAR, $tmpfname);
curl_setopt($ch, CURLOPT_COOKIEFILE, $tmpfname);