点击删除时，显示删除成功，但是并没有删除！我是按着老师步骤来的啊！求救！
<?php
header("Content-Type:text/html; charset=utf8");
class UserAction extends Action{
public function info(){
$user =M('user');
$list =$user->field(array('user_id','user_name','email'))->select();
$this->assign('alist',$list);

$this->display();
}
public function delinfo(){
$user=M('user');
if($user->delete($_GET['user_id'])){
$this->success('删除成功');
}
else
{
$this->error('删除失败');
}

$this->display();
}
}