Yii confirm弹框不弹出怎么办？

// 原代码Html::a(Yii::t('app','Delete'), ['delete', 'id' => $model->id], [    'class' => 'btn btn-danger',    'data' => [        'confirm' => 'Are you sure you want to delete this item?',        'method' => 'post',    ],])// 修改后的代码Html::a(Yii::t('app','Delete'), ['delete', 'id' => $model->id], ['class' => 'btn btn-danger', 'data-confirm' => 'Are you sure you want to delete this item?'])