用PHP模拟登陆_php教程_php教程

经常会有人问php模拟登陆的问题，其实原理很简单，只要把SessionID保存下来就可以了，今天花了一个小时的时间写了一个函数，供大家参考,网站返回的头信息，具体网站具体分析,源代码：

<?php

* 得到网页内容

* 参数：$host [in] string

* 主机名称（例如： www.etoow.com）

* 参数：$method [in] string

* 提交方法：POST, GET, HEAD ... 并加上相应的参数( 具体语法参见 RFC1945，RFC2068 )

* 参数：$str [in] string

* 提交的内容

* 参数：$sessid [in] string

* PHP的SESSIONID

* @返回网页内容 string

function GetWebContent($host, $method, $str, $sessid = '')

{

$ip = gethostbyname($host);

$fp = fsockopen($ip, 80);

if (!$fp) return;

fputs($fp, "$methodrn");

fputs($fp, "Host: $hostrn");

if (!emptyempty($sessid))

{

fputs($fp, "Cookie: PHPSESSID=$sessid; path=/;rn");

}

if ( substr(trim($method),0, 4) == "POST")

{

fputs($fp, "Content-Length: ". strlen($str) . "rn"); // 别忘了指定长度

}

fputs($fp, "Content-Type: application/x-www-form-urlencodedrnrn");

if ( substr(trim($method),0, 4) == "POST")

{

fputs($fp, $str."rn");

}

while(!feof($fp))

{

$response .= fgets($fp, 1024);

}

$hlen = strpos($response," "); // LINUX下是 " "

$header = substr($response, 0, $hlen);

$entity = substr($response, $hlen 4);

if ( preg_match('/PHPSESSID=([0-9a-z] );/i', $header, $matches))

{

$a['sessid'] = $matches[1];

}

if ( preg_match('/Location: ([0-9a-z_?=&#.] )/i', $header, $matches))

{

$a['location'] = $matches[1];

}

$a['content'] = $entity;

fclose($fp);

return $a;

}

/* 构造用户名，密码字符串 */

$str = ("username=test&password=test");

$response = GetWebContent("localhost","POST /login.php HTTP/1.0", $str);

echo $response['location'].$response['content']." ";

echo $response['sessid']." ";

if ( preg_match('/error.php/i',$response['location']))

{

echo "登陆失败 ";

} else {

echo "登陆成功 ";

// 不可以访问user.php，因为不带sessid参数

$response = GetWebContent("localhost","GET /user.php HTTP/1.0", '', '');

echo $response['location']." "; // 结果：error.php?errcode=2

// 可以访问user.php

$response = GetWebContent("localhost","GET /user.php HTTP/1.0", '', $response['sessid']);

echo $response['location']." "; // 结果：user.php

}

(责任编辑：最模板)