title: PrestaShop - Reload CMS page with additional parameters
body: <p><strong>Situation</strong>: I needed to add form with POST method to CMS page. I created custom hook and a module displaying the form successfully. Then I need to react to user input errors eg. when user doesn't enter email address I need to detect it, display the whole page again together with the form and with "errors" in user input clearly stated.</p>
  
  <p><strong>Problem</strong>: The problem is to display the WHOLE page again with connected information (eg. about errors etc.). In the module PHP file when I add this kind of code,</p>
  
  <pre><code>return $this-&gt;display(__FILE__, 'modulename.tpl');
  </code></pre>
  
  <p>it (naturally) displays ONLY the form, not the whole CMS page with the form.</p>
  
  <p>In case of this code,</p>
  
  <pre><code>Tools::redirectLink('cms.php?id_cms=7');
  </code></pre>
  
  <p>I can't get to transfer any information by GET neither POST method.</p>
  
  <pre><code>$_POST['test'] = 1;
  Tools::redirectLink('cms.php?id_cms=7&amp;test');
  </code></pre>
  
  <p>I tried to assign to smarty variables too</p>
  
  <pre><code>$smarty-&gt;assign('test', '1');
  </code></pre>
  
  <p>(I need to use it in .tpl file where the form itself is created) but no way to get it work.</p>
  
  <pre><code>{if isset($test)}...,
  {if isset($smarty.post.test)}...,
  {if isset($_POST['test'])}... {* neither of these conditionals end up as true *}
  </code></pre>
  
  <p>Even assigning a GET parameter to url has no impact, because there is link rewriting to some kind of friendly url I guess, no matter I included other argument or not. (<code>[SHOPNAME]/cms.php?id_cms=7&amp;test</code> -> <code>[SHOPNAME]/content/7-cmspage-name</code>)</p>
  
  <p><strong>My question is</strong>: is there a way to "redirect" or "reload" current page (or possibly any page generally) in prestashop together with my own data included?</p>
  
  <p>I kind of explained the whole case so I'm open to hear a better overall solution than my (maybe I'm thinking about the case in a wrong way at all). This would be other possible answer.</p>