这个问题折磨了好久，今天特意抽出一些时间来看看discuz的源代码，将部分代码抽取出来，写成函数，这样以后登录与退出只要调用一下这两个函数就可以了。
//退出Discuz账号
function discuz_logout(){
require './bbs/source/class/class_core.php'; //引入系统核心文件
$discuz = & discuz_core::instance(); //以下代码为创建及初始化对象
$discuz->cachelist = $cachelist;
$discuz->init();
require libfile('function/member');
require libfile('class/member');
$_GET['formhash'] = $_G['formhash'];
$ctl_obj = new logging_ctl();
$ctl_obj->setting = $_G['setting'];
$method = 'on_logout';
//$ctl_obj->template = 'member/login';
$ctl_obj->$method();
echo "成功退出！".time();
}
//登录Discuz账号
function discuz_login($username,$password){
require 'E:/ku25.com/wwwroot/bbs/source/class/class_core.php'; //引入系统核心文件
$discuz = & discuz_core::instance(); //以下代码为创建及初始化对象
$discuz->cachelist = $cachelist;
$discuz->init();
require libfile('function/member');
require libfile('class/member');
$_GET['formhash'] = $_G['formhash'];
$_GET['from'] = 1;
$_GET['loginsubmit'] = $_GET['infloat'] = 'yes';
$_GET['cookietime'] = '2592000';
$_GET['username'] = $username;
$_GET['password'] = $password;
$ctl_obj = new logging_ctl();
$ctl_obj->setting = $_G['setting'];
$method = 'on_login';
//$ctl_obj->template = 'member/login';
$ctl_obj->$method();
echo "成功登录！".time();
}