public function login(){

    if(!IS_POST){echo "页面不存在"; $this->redirect('index'); die();};

    $username = I('post.username');

    $pwd = I('post.password','','md5');

    $code = I('post.code');

    $obj = new \Think\Verify();

    if(!$obj->check($code)){

        $this->error('验证码错误');

    };

    //验证账号和密码

    $where = array(

        'account' => $username

    );

    $result = M('admin')->where($where)->find();

    if(!$result || $result['password'] != $pwd){

         $this->error('账号或密码错误');

    };

    if($user['lock']){

        $this->error('账号被锁定');

    };

    $data = array(

        'id' => $result['id'],

        'logintime' => time(),

        'loginIp' => get_client_ip()

    );

    M('admin')->save($data);

    // 存session

    session('uid',$result['id']);

    session('uid',$result['account']);

    session('logintime',date('y-m-d H:i',$result['logintime']));

    session('loginip',$result['loginip']);

    $this->redirect('/admin/index','',2,'页面正在跳转中...');

}