yii2组件之下拉框带搜索功能的示例代码（yii-select2）

//controller层
public function actionSearchTitle ($q)
{
  \Yii::$app->response->format = \yii\web\Response::FORMAT_JSON;
  $out = ['results' => ['id' => '', 'text' => '']];
  if (!$q) {
    return $out;
  }

  $data = Article::find()
        ->select('id, title as text')
        ->andFilterWhere(['like', 'title', $q])
        ->limit(50)
        ->asArray()
        ->all();
        
  $out['results'] = array_values($data);

  return $out;
}