PHP如何使用curl模拟登陆？

$ch = curl_init();$url = " 
$data = array(    'mail' => ***    'password' => ***
);
foreach ($data as $key => $value){    
$postfields .= urlencode($key) . '=' . urlencode($value) . '&';
}$postfields = rtrim($postfields, '&');$headers = array(    'Accept:*/*',    
'Accept-Encoding:gzip, deflate',    'Accept-Language:zh-CN,zh;q=0.8',    
'Connection:keep-alive',    'Content-Length:49',   
 'Content-Type:application/x-www-form-urlencoded; charset=UTF-8', 
 'Cookie:mp_18fe57584af9659dea732cf41c1c0416_mixpanel=
 %7B%22distinct_id%22%3A%20%22153c6c3ec0c91-04fd9c038-12771e2d-1fa400-153c6c3ec0d18a%22%2C%22%24
 initial_referrer%22%3A%20%22%24direct%22%2C%22%24initial_referring_domain%22%3A%20%22%24direct%22%7D; 
 PHPSESSID=web2~dom8lkdgosec57oljs98g2m8k0; 
 _gat=1; 
 Hm_lvt_e23800c454aa573c0ccb16b52665ac26=1463986883,1464937399,1465290769,1465713371; 
 Hm_lpvt_e23800c454aa573c0ccb16b52665ac26=1465717067; 
 _ga=GA1.2.1469164019.1455850659',    
 'Host:segmentfault.com',    
 'Origin:https://segmentfault.com',   
  'Referer:https://segmentfault.com/',    
  'User-Agent:Mozilla/5.0 (X11; Linux i686 (x86_64)) AppleWebKit/537.36 (KHTML, like Gecko) 
  Chrome/48.0.2564.97 Safari/537.36',    'X-Requested-With:XMLHttpRequest',
);

curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_POST, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
curl_setopt($ch, CURLOPT_POSTFIELDS, $postfields);
curl_setopt($ch, CURLOPT_ENCODING, "");$result = curl_exec($ch);
curl_close($ch);
var_dump($result);

<script crossorigin src="https://dfnjy7g2qaazm.cloudfront.net/v-575e20ec/user/script/login.min.js"></script>

$("form[action='/api/user/login']").submit(function() {  var data, url;
  url = '/api/user/login';
  data = $(this).serialize();
  $.post(url, data, function(d) {    if (!d.status) {      return location.href = d.data;
    }
  });  return false;
});

POST /api/user/login?_=93e1b923149fb56c4fd329fe95ea4001 HTTP/1.1
Host: segmentfault.com
Connection: keep-alive
Content-Length: 46
Pragma: no-cache
Cache-Control: no-cache
Accept: */*
Origin: https://segmentfault.com
X-Requested-With: XMLHttpRequest
User-Agent: xxxx
Content-Type: application/x-www-form-urlencoded; charset=UTF-8
DNT: 1
Referer: https://segmentfault.com/
Accept-Encoding: gzip, deflate, br
Accept-Language: en-US,en;q=0.8,zh-CN;q=0.6,zh;q=0.4
Cookie: PHPSESSID=web5~to8l5ovmt9t3jkb84aevuqf151; 
Hm_lvt_e23800c454aa573c0ccb16b52665ac26=1465799317; 
Hm_lpvt_e23800c454aa573c0ccb16b52665ac26=1465799317;
 _ga=GA1.2.915515414.1465799317; _gat=1

var superagent = require('superagent');


superagent.post('https://segmentfault.com/api/user/login?_=7ef046ad4f224034d7b51655238bd870')
    .set('Referer', 'https://segmentfault.com/user/login')
    .set('X-Requested-With', 'XMLHttpRequest')
    .set('Cookie', 'PHPSESSID=web1~395mahoqliohh5kclv894ibpr3; _gat=1; 
    _ga=GA1.2.1234754628.1465797373; Hm_lvt_e23800c454aa573c0ccb16b52665ac26=1465797373; 
    Hm_lpvt_e23800c454aa573c0ccb16b52665ac26=1465797538')
    .send({
        mail: "xxxxxx",
        password: "xxxx"
    })
    .type('form')
    .end(function(err, res) {        if (err || !res.ok) {            console.log(err.status);
        } else {            console.log('yay got ' + JSON.stringify(res.body));
        }
    });