title: Yii2: Proper way of writting the form's action
body: <p>I have written form tag of YII2 specific as </p>
  
  <pre><code>&lt;?php $form = ActiveForm::begin(['id' =&gt; 'builder/saveform','options' =&gt; ['method' =&gt; 'post']]) ?&gt;
  </code></pre>
  
  <p>but when i run this, my external javascript is catching an error showing </p>
  
  <pre><code>Error: Syntax error, unrecognized expression: #builder/saveform
  </code></pre>
  
  <p>What is the error</p>