title: form sending null value to the controller in yii2
body: <p>here is my form and I'm sending it to the controller to get the data and insert it to the db with model but when I'm checking the post data in the controller it is null . here is my form :</p>
  
  <pre><code>&lt;div class="container"&gt;
     &lt;div class="row"&gt;
     &lt;div class="col-md-12" &gt;
                 &lt;div class="widget-area no-padding blank"&gt;
                 &lt;div class="status-upload"&gt;
                   &lt;?php
                   $form = ActiveForm::begin([
                     'action' =&gt; ['twit/send-twit'],
                   ]);
                   ?&gt;
                    &lt;?= $form-&gt;field($model,'twit')-&gt;textarea(); ?&gt;
                     &lt;?= Html::SubmitButton('ارسال',['class' =&gt; 'btn btn-success green']); ?&gt;
                   &lt;?php ActiveForm::end(); ?&gt;
                 &lt;/div&gt;&lt;!-- Status Upload  --&gt;
               &lt;/div&gt;&lt;!-- Widget Area --&gt;
             &lt;/div&gt;
     &lt;/div&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>and here is my controller which I'm checking the value of the posted field (twit) and it is always null :</p>
  
  <pre><code>    public function actionSendTwit()
      {
          $request = Yii::$app-&gt;request;
  var_dump($request-&gt;post('twit'));
  die();
          if ($request-&gt;post('twit')){
              $twitContent = $request-&gt;post('twit');
              Twit::sendTwit($twitContent);
              \yii::$app-&gt;response-&gt;redirect('?r=twit/index',301)-&gt;send();
          }
  
      }
  </code></pre>