title: In Yii framework how can I Combine columns and show as display string in dropdownlist
body: <p>I have a <code>dropDownList</code> in my view, it is populating from <code>clients</code> table, the table contains columns like <code>first_name</code>, <code>last_name</code>,<code>id</code> etc., Now I want to show the <code>first_name</code> and <code>last_name</code> as display text and <code>id</code> as value in drop down list, I'm done with <code>id</code> as value and <code>first_name</code> as display text, but here I want to combine those columns (<code>first_name</code> and <code>last_name</code>) and use as display text.</p>
  
  <p><strong>in model</strong></p>
  
  <pre><code>function getClients()
  {
      $Clients = Client::model()-&gt;findAll();
      $list    = CHtml::listData($Clients , 'client_id', 'first_name');
      return $list;
  }
  </code></pre>
  
  <p><strong>in view</strong></p>
  
  <pre><code>echo $form-&gt;dropDownList($model,'client_id',$model-&gt;getClients());
  </code></pre>