Code about Yii2.0 multi-file upload

<?php 
namespace frontend\controllers;
use Yii;
use yii\web\Controller;
use frontend\models\Uploadm;
use yii\web\UploadedFile;
class FormController extends Controller{
  public function actionMyfiles(){
      $model=new Uploadm();
      return $this->renderPartial(&#39;myfiles&#39;,[&#39;model&#39;=>$model]);
  }
  public function actionGetfiles(){
    $model = new Uploadm();
    if (Yii::$app->request->isPost) {
      $model->imgFile = UploadedFile::getInstances($model, &#39;imgFile&#39;);
      if ($model->upload()) {
        // 文件上传成功
        echo &#39;上传成功&#39;;
      }
    }
  }

<?php
namespace frontend\models;
use Yii;
use yii\base\Model;
use yii\web\UploadedFile;
class Uploadm extends Model
{
  public $imgFile;
  public function rules(){
    return [
       [[&#39;imgFile&#39;], &#39;file&#39;,&#39;maxFiles&#39; => 5],//最多5张
    ];
  }
  public function upload()
  {
   if ($this->validate()) { 
     foreach ($this->imgFile as $file) {
       $file->saveAs(&#39;uploads/&#39; . $file->baseName . &#39;.&#39; . $file->extension);
     }
     return true;
   } else {
     return false;
   }
  }
}

<?php
use yii\helpers\Html;
use yii\widgets\ActiveForm;
$form = ActiveForm::begin([
  &#39;id&#39; => &#39;login-form&#39;,
  &#39;options&#39; => [&#39;class&#39; => &#39;form-horizontal&#39;,&#39;enctype&#39; => &#39;multipart/form-data&#39;],
  &#39;action&#39;=>&#39;?r=form/getfiles&#39;,
  &#39;method&#39;=>&#39;post&#39;
]) ?>
  <?= $form->field($model, &#39;imgFile[]&#39;)->fileInput([&#39;multiple&#39; => true]) ?>

  <p class="form-group">
    <p class="col-lg-offset-1 col-lg-11">
      <?= Html::submitButton(&#39;上传&#39;, [&#39;class&#39; => &#39;btn btn-primary&#39;]) ?>
    </p>
  </p>
<?php ActiveForm::end() ?>