Yii2 get post request value not working
<p>Why <code>Yii::$app-&gt;request-&gt;post()</code> not working?</p>

<p>Form:</p>

<pre><code> &lt;?php $form = ActiveForm::begin(); ?&gt;

   &lt;?= $form-&gt;field($model, 'parent')
        -&gt;dropDownList($model-&gt;AuthItemDropdown
        );
    ?&gt;
    &lt;?= $form-&gt;field($model, 'child[]')
        -&gt;dropDownList($model-&gt;AuthItemDropdown,
            ['multiple'=&gt;'multiple']  
        );
    ?&gt;
</code></pre>

<p>Controller:</p>

<pre><code> public function actionCreate(){

    $model = new AuthItemChild();

    if ($model-&gt;load(Yii::$app-&gt;request-&gt;post())){

        $parent =  Yii::$app-&gt;request-&gt;post('parent');
        echo $parent; // show nothing

        $x = Yii::$app-&gt;request-&gt;post('child');
        print_r($x);// show nothing
        exit;
</code></pre>

<p>But output of <code>print_r(Yii::$app-&gt;request-&gt;post());</code> is:</p>

<pre><code>Array
(
    [_csrf-backend] =&gt; OGd0emxoOHgJEh8ICFloPlYvJg8BEHk.VjVAMx0hTD9CKgIDNSdVOg==
    [AuthItemChild] =&gt; Array
        (
            [parent] =&gt; admin
            [child] =&gt; Array
                (
                    [0] =&gt; admin
                    [1] =&gt; create-branch
                )
        )
)
</code></pre>