【php获取网页请求状态码】php获取网页请求状态程序代码

【www.bbyears.com--php常用代码】

方法一，使用 fsockopen

严重鄙视curl_getinfo!

function get_http_code($url="localhost", $port=80, $fsock_timeout=10){
    set_time_limit(0);
    ignore_user_abort(true);
 
    // 记录开始时间
    list($usec, $sec) = explode(" ", microtime(true));
    $timer["start"] = (float)$usec + (float)$sec;
 
    // 校验URL
    if(!preg_match("/^https?:＼/＼//i", $url)){
        $url = "http://".$url;
    }
    // 支持HTTPS
    if(preg_match("/^https:＼/＼//i", $url)){
        $port = 443;
    }
 
    // 解析URL
    $urlinfo = parse_url($url);
    if(empty($urlinfo["path"])){
        $urlinfo["path"] = "/";
    }
    $host = $urlinfo["host"];
    $uri = $urlinfo["path"] . (empty($urlinfo["query"])?"":$urlinfo["query"]);
 
    // 通过fsock打开连接
    if(!$fp = fsockopen($host, $port, $errno, $error, $fsock_timeout)){
        list($usec, $sec) = explode(" ", microtime(true));
        $timer["end"] = (float)$usec + (float)$sec;
        $usetime = (float)$timer["end"] - (float)$timer["start"];
 
        return array("code"=>-1, "usetime"=>$usetime);
    }
 
    // 提交请求
    $status = socket_get_status($fp);
    $out = "GET {$uri} HTTP/1.1＼r＼n";
    $out .= "Host: {$host}＼r＼n";
    $out .= "Connection: Close＼r＼n＼r＼n";
    $write = fwrite($fp, $out);
    if(!$write){
        list($usec, $sec) = explode(" ", microtime(true));
        $timer["end"] = (float)$usec + (float)$sec;
        $usetime = (float)$timer["end"] - (float)$timer["start"];
 
        return array("code"=>-2, "usetime"=>$usetime);
    }
 
    $ret = fgets($fp, 1024);
    preg_match("/http＼/＼d＼.＼d＼s(＼d+)/i", $ret, $m);
    $code = $m[1];
    fclose($fp);
 
    list($usec, $sec) = explode(" ", microtime(true));
    $timer["end"] = (float)$usec + (float)$sec;
    $usetime = (float)$timer["end"] - (float)$timer["start"];
 
    return array("code"=>$code, "usetime"=>$usetime);
}

file_get_contents 是 fsockopen 功能的简单打包，效率稍低些，但是抓取成功率很高，所以在 snoopy 出问题的时候我一般那他来。5.0.0 添加了对 context 的支持，有了context，他也可以发送 header 信息，自定义用户 agent, referer, cookies 都不在话下。5.1.0 添加了 offset 和 maxlen 参数，可以只读文件的一部分内容。

方法二，使用snoopy.class.php

Snoopy是一个php类，用来模拟浏览器的功能，可以获取网页内容，发送表单。

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://www.spiegel.de/");
curl_setopt($ch, CURLOPT_RANGE, "0-500");
curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
$result = curl_exec($ch);
curl_close($ch);
echo $result;
/**
*But as noted before if the server doesn"t honor this header but sends the whole file curl will download all of it. E.g. http://www.111cn.net ignores the header. But you can (in addition) set a write function callback and abort the request when more data is received, e.g.
* php 5.3+ only
* use function writefn($ch, $chunk) { ... } for earlier versions
*/
$writefn = function($ch, $chunk) {
  static $data="";
  static $limit = 500; // 500 bytes, it"s only a test
  $len = strlen($data) + strlen($chunk);
  if ($len >= $limit ) {
    $data .= substr($chunk, 0, $limit-strlen($data));
    echo strlen($data) , " ", $data;
    return -1;
  }
  $data .= $chunk;
  return strlen($chunk);
};
$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, "http://www.111cn.net/");
curl_setopt($ch, CURLOPT_RANGE, "0-500");
curl_setopt($ch, CURLOPT_BINARYTRANSFER, 1);
curl_setopt($ch, CURLOPT_WRITEFUNCTION, $writefn);
$result = curl_exec($ch);
curl_close($ch);

一些常见的状态码为：

200 - 服务器成功返回网页
404 - 请求的网页不存在
503 - 服务器超时
301 - 页面重定向

本文来源：http://www.bbyears.com/jiaocheng/53997.html