模拟登陆正方教务系统，重定向一直解决不了〉

<?php$login_url='http://jwxt.nbut.cn/(gnqj51blynlz1k45ufftjgux)/default_ysdx.aspx';$user='11480010126';$password='tianyun';$radiobuttonlist1='学生';$__viewstate='ddw1mjq2odmxnzy7oz5pmj6wmevizgwygp6ts4slvnqtaa=='; $cookie_file = tempnam('./temp','cookie');$login_url = 'http://jwxt.nbut.cn/(gnqj51blynlz1k45ufftjgux)/default_ysdx.aspx';$post_fields = array($user,$password,$radiobuttonlist1,$__viewstate);//传入参数$ch = curl_init($login_url);curl_setopt($ch, curlopt_header, 0);//显示头部curl_setopt($ch, curlopt_post, 1);//post传递$header[]='user-agent:mozilla/5.0 (windows nt 6.1; wow64) applewebkit/537.36 (khtml, like gecko) chrome/34.0.1847.116 safari/537.36';curl_setopt($ch, curlopt_httpheader, $header);//模拟客户端curl_setopt($ch, curlopt_returntransfer,0);//显示页面curl_setopt($ch, curlopt_postfields, $post_fields);//post传递值curl_setopt($ch, curlopt_cookiejar, $cookie_file);//存入cookiecurl_setopt($ch, curlopt_followlocation, 1);//允许重定向curl_exec($ch);curl_close($ch);     $url='http://jwxt.nbut.cn/(gnqj51blynlz1k45ufftjgux)/xs_main.aspx?xh='.$user;$ch = curl_init($url);curl_setopt($ch, curlopt_header, 0);curl_setopt($ch, curlopt_returntransfer, 0);curl_setopt($ch, curlopt_followlocation, 1);curl_setopt($ch, curlopt_post, 1);$header[]='referer:http://jwxt.nbut.cn/(gnqj51blynlz1k45ufftjgux)/default_ysdx.aspx';$header[]='user-agent:mozilla/5.0 (windows nt 6.1; wow64) applewebkit/537.36 (khtml, like gecko) chrome/34.0.1847.116 safari/537.36';curl_setopt($ch, curlopt_httpheader, $header);curl_setopt($ch, curlopt_cookiefile, $cookie_file);//读取cookieecho $contents;$contents = curl_exec($ch);curl_close($ch); ?>

$url = 'http://jwxt.nbut.cn';$u = get_headers($url, 1);$login_url = 'http://jwxt.nbut.cn' . dirname($u['Location']) . '/default_ysdx.aspx';

$post_fields = array(  'TextBox1' => $user = '11480010126',  'TextBox2' => 'tianyun',  'RadioButtonList1' => '学生',  '__VIEWSTATE' => 'dDw1MjQ2ODMxNzY7Oz5PMj6WMeVIzgWyGp6TS4sLvnQtaA==',  "Button1" => "  登录  ",);