方法一:

$baiduUrl = "http://www.baidu.com/link";
 
file_get_contents($baiduUrl);
$responseInfo = $http_response_header;
 
print_r($responseInfo);
// 输出:
Array
(
    [0] => HTTP/1.1 302 Found
    [1] => Date: Fri, 27 Jun 2014 02:47:35 GMT
    [2] => Server: Apache
    [3] => Location: http://www.edeng.cn/s/chuna/
    [4] => Cache-Control: max-age=86400
    [5] => Expires: Sat, 28 Jun 2014 02:47:35 GMT
    [6] => Content-Length: 212
    [7] => Connection: Close
    [8] => Content-Type: text/html; charset=iso-8859-1
    [9] => HTTP/1.1 200 OK
    [10] => Server: nginx/1.4.3
    [11] => Date: Fri, 27 Jun 2014 02:47:35 GMT
    [12] => Content-Type: text/html; charset=utf-8
    [13] => Connection: close
    [14] => Expires: Mon, 26 Jul 1997 05:00:00 GMT
    [15] => Last-Modified: Fri, 27 Jun 2014 02:47:35 GMT
    [16] => Cache-Control: no-store, no-cache, must-revalidate
    [17] => Pragma: no-cache
    [18] => Vary: User-Agent,Accept-Encoding
    [19] => X-Cache: MISS from web1.edeng.cn
    [20] => Via: 1.1 web1.edeng.cn:80 (squid)
)
 
遍历该数组即可得到相应的值。比如要想获得 Location 的值:
 
foreach ($responseInfo as $loop) {
if(strpos($loop, "Location") !== false){
$edengUrl = trim(substr($loop, 10));
print_r($edengUrl);
// 输出: http://www.edeng.cn/s/chuna/
}
}
 
方法二:
==========================================
function get_head($sUrl){
$oCurl = curl_init();
// 设置请求头, 有时候需要,有时候不用,看请求网址是否有对应的要求
$header[] = "Content-type: application/x-www-form-urlencoded";
$user_agent = "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.146 Safari/537.36";
 
curl_setopt($oCurl, CURLOPT_URL, $sUrl);
curl_setopt($oCurl, CURLOPT_HTTPHEADER,$header);
// 返回 response_header, 该选项非常重要,如果不为 true, 只会获得响应的正文
curl_setopt($oCurl, CURLOPT_HEADER, true);
// 是否不需要响应的正文,为了节省带宽及时间,在只需要响应头的情况下可以不要正文
curl_setopt($oCurl, CURLOPT_NOBODY, true);
// 使用上面定义的 ua
curl_setopt($oCurl, CURLOPT_USERAGENT,$user_agent);
curl_setopt($oCurl, CURLOPT_RETURNTRANSFER, 1 );
// 不用 POST 方式请求, 意思就是通过 GET 请求
curl_setopt($oCurl, CURLOPT_POST, false);
 
$sContent = curl_exec($oCurl);
// 获得响应结果里的:头大小
$headerSize = curl_getinfo($oCurl, CURLINFO_HEADER_SIZE);
// 根据头大小去获取头信息内容
$header = substr($sContent, 0, $headerSize);
    
curl_close($oCurl);
 
return $header;
}
 
如上面解析,我们可以成功获得到头信息:
HTTP/1.1 302 Found
Date: Fri, 27 Jun 2014 02:47:35 GMT
Server: Apache
Location: http://www.edeng.cn/s/chuna/
Cache-Control: max-age=86400
Expires: Sat, 28 Jun 2014 02:47:35 GMT
Connection: Keep-Alive
Content-Type: text/html; charset=iso-8859-1
 
这时候,如果我们想获得 Location  项的内容,可以先把上面头正文件按回车换行切割成数组,然后再遍历匹配,如:
$responseHead = post_head($baiduUrl);
 
$headArr = explode("\r\n", $responseHead);
foreach ($headArr as $loop) {
if(strpos($loop, "Location") !== false){
$edengUrl = trim(substr($loop, 10));
print_r($edengUrl);
// 输出: http://www.edeng.cn/s/chuna/
}
}