yii报错及bug修复：Yii与vue交互 No 'Access-Control-Allow-Origin' header is present on....

在后端该controller里申明

public function behaviors()
{
            return ArrayHelper::merge([
            [
                'class' => Cors::className(),
                'cors' => [
                    'Origin' => ['http://localhost:8080'],
                    // 'Origin' => ['*'],
                    'Access-Control-Request-Method' => ['POST'],
                    'Access-Control-Allow-Credentials' => true,
                ],
            ],
        ], parent::behaviors());
}

注意use以下两个文件：

use yii\helpers\ArrayHelper;
use yii\filters\Cors;