title: Symfony2 - form_start function customise in twig
body: <p>Form helpers <code>form_start</code> and <code>form_end</code> are useful in twig:</p>
  
  <pre><code>{{ form_start(form) }}
  {{ form_end(form) }}
  </code></pre>
  
  <p>I can customise some parameters like the <code>method</code> or the <code>action</code>. But I need to customise others parameters like the <code>class</code> or add the <code>form-enctype</code>.</p>
  
  <p>Can I do it? Should i set up it into the <code>FormType.php</code>?</p>
  
  <p>Since now I simply try to add my customised value to the <code>twig</code> function like below:</p>
  
  <pre><code>{{ form_start(form, {'class': 'myclass', 'action': 'myaction'}) }}
  // fields...
  {{ form_end(form, {'render_rest': true}) }}
  </code></pre>
  
  <p>But in this case, for example, the <code>class</code> does not appear.</p>