public function createToken($uid, $token_expire = 0)
{
$token_expire = $token_expire > 0 ? time() + $token_expire : time() + 60 * 60 * 24 * 90;
$token = md5(md5($uid . $token_expire . time() . rand() . "showdoc") . "rdgtrd12367hghf54t");
$data['uid'] = $uid;
$data['token'] = $token;
$data['token_expire'] = $token_expire;
$data['ip'] = getIPaddress();
$data['addtime'] = time();
$ret = $this->add($data);
if ($ret) {
//删除过期的token
$this->where("token_expire < " . time())->delete();
return $token;
}
return false;
}