用php curl模拟登陆discuz论坛

!extension_loaded('curl') && die('The curl extension is not loaded.');    
   
$discuz_url = '';//论坛地址    
$login_url = $discuz_url .'';//登录页地址    
   
$post_fields = array();    
//以下两项不需要修改    
$post_fields['loginfield'] = 'username';    
$post_fields['loginsubmit'] = 'true';    
//用户名和密码，必须填写    
$post_fields['username'] = '';    
$post_fields['password'] = '';    
//安全提问    
$post_fields['questionid'] = 0;    
$post_fields['answer'] = '';    
//@todo 验证码    
$post_fields['seccodeverify'] = '';    
   
//获取表单FORMHASH    
$ch = curl_init($login_url);    
curl_setopt($ch, CURLOPT_HEADER, 0);    
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);    
$contents = curl_exec($ch);    
curl_close($ch);
preg_match('/<input\s*type="hidden"\s*name="formhash"\s*value="(.*?)"\s*\/>/i', $contents, $matches);
if(!empty($matches)) {    
    $formhash = $matches[1];    
} else {    
    die('Not found the forumhash.');    
}    
   
//POST数据，获取COOKIE    
$cookie_file = dirname(__FILE__) . '/cookie.txt';    
//$cookie_file = tempnam('/tmp');    
$ch = curl_init($login_url);    
curl_setopt($ch, CURLOPT_HEADER, 0);    
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);    
curl_setopt($ch, CURLOPT_POST, 1);    
curl_setopt($ch, CURLOPT_POSTFIELDS, $post_fields);    
curl_setopt($ch, CURLOPT_COOKIEJAR, $cookie_file);    
curl_exec($ch);    
curl_close($ch);    
   
//带着上面得到的COOKIE获取需要登录后才能查看的页面内容    
$ch = curl_init('http://www.belle8.com/thread-758357-1-1.html');    
curl_setopt($ch, CURLOPT_HEADER, 0);    
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 0);    
curl_setopt($ch, CURLOPT_COOKIEFILE, $cookie_file);    
$contents = curl_exec($ch);    
curl_close($ch);