YII2 在grid表里给字段值加 下载附件链接 表内字段值回调

一、视图层

[
        'attribute' => 'purchaseFile',
        'hAlign' => 'center',
        'vAlign'=>'middle',
       //以下是加链接动作，及其样式（其他动作同理）
        'format' => 'raw',
        'value'=> function($model){
            return Html::a($model->purchaseFile, 
                [
                'download',
                'id'=>$model->purchaseID
                ], [
                'title' => '下载附件',
                'data' => [
                    'method' => 'post',//一定要注明post方式！！
                        ]
                ]);
        }
    ]

二、控制器相应

 //下载附件
    public function actionDownload($id)
    {
        $model = $this->findModel($id);
        if($model->purchaseFile){
           $all = Purchase::find()
                    ->where(['purchaseID'=>$id])
                    ->asArray()
                    ->one();
           $fileName = $all['fileName'];
            //查找路径并下载
           if (file_exists('../uploads/purchaseFile/' . $fileName)) {
                return Yii::$app->response->sendFile('../uploads/purchaseFile/' . $fileName)->send();
           } else {
                return "<h1>文件不存在</h1>";
            }
        }else{
            Yii::$app->session->setFlash('error', '不存在采购附件');
            return $this->redirect(['index', 'id' => $model->purchaseID]);
        }