/**
  * Action: Delete my comments
  * @return Response
  */
 public function deleteComment($id)
 {
     // Delete operations only allow comments to yourself
     $comment = ProductComment::where('id', $id)->where('user_id', Auth::user()->id)->first();
     if (is_null($comment)) {
         return Redirect::back()->with('error', '没有找到对应的评论');
     } elseif ($comment->delete()) {
         return Redirect::back()->with('success', '评论删除成功。');
     } else {
         return Redirect::back()->with('warning', '评论删除失败。');
     }
 }