Can not fetch value of an element using Symfony Dom Crawler - php

Question

I am fetching a URL using guzzle POST method . its working and returning the page that I want . but the problem is when I want to get the value of an input element in a form in that page, the crawler returns nothing . I don't know why .
PHP:
<?php
use Symfony\Component\DomCrawler\Crawler;
use Guzzle\Http\Client;
$client = new Client();
$request = $client->get("https://example.com");
$response = $request->send();
$getRequest = $response->getBody();
$cookie = $response->getHeader("Set-Cookie");
$request = $client->post('https://example.com/page_example.php', array(
'Content-Type' => 'application/x-www-form-urlencoded',
'Cookie' => $cookie
), array(
'param1' => 5,
'param2' => 10,
'param3' => 20
));
$response = $request->send();
$pageHTML = $response->getBody();
//fetch orderID
$crawler = new Crawler($pageHTML);
$orderID = $crawler->filter("input[name=orderId]")->attr('value');//there is only one element with this name
echo $orderID; //returns nothing
What should I do ?

Answer 1

You don't have to create a Crawler:
$crawler = $client->post('https://example.com/page_example.php', array(
'Content-Type' => 'application/x-www-form-urlencoded',
'Cookie' => $cookie
), array(
'param1' => 5,
'param2' => 10,
'param3' => 20
));
$orderID = $crawler->filter("input[name=orderId]")->attr('value');
This assumes your POST isn't being redirected, if it is redirected you should add before calling the filter function:
$this->assertTrue($client->getResponse()->isRedirect());
$crawler = $client->followRedirect();