php结合curl实现多线程抓取

2020-03-22 17:39:51

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curl_setopt($conn[$k], CURLOPT_TIMEOUT, $timeout);//设置超时时间 curl_setopt($conn[$k], CURLOPT_USERAGENT, 'Mozilla/5.0 (compatible; MSIE 5.01; Windows NT 5.0)'); curl_setopt($conn[$k], CURLOPT_MAXREDIRS, 7);//HTTp定向级别 curl_setopt($conn[$k], CURLOPT_HEADER, 0);//这里不要header，加块效率 curl_setopt($conn[$k], CURLOPT_FOLLOWLOCATION, 1); // 302 redirect curl_setopt($conn[$k],CURLOPT_RETURNTRANSFER,1); curl_multi_add_handle ($mh,$conn[$k]); //防止死循环耗死cpu 这段是根据网上的写法 do { $mrc = curl_multi_exec($mh,$active);//当无数据，active=true } while ($mrc == CURLM_CALL_MULTI_PERFORM);//当正在接受数据时 while ($active and $mrc == CURLM_OK) {//当无数据时或请求暂停时，active=true if (curl_multi_select($mh) != -1) { do { $mrc = curl_multi_exec($mh, $active); } while ($mrc == CURLM_CALL_MULTI_PERFORM); foreach ($array as $k = $url) { curl_error($conn[$k]); $res[$k]=curl_multi_getcontent($conn[$k]);//获得返回信息 $header[$k]=curl_getinfo($conn[$k]);//返回头信息 curl_close($conn[$k]);//关闭语柄 curl_multi_remove_handle($mh , $conn[$k]); //释放资源 curl_multi_close($mh); $endtime = getmicrotime(); $diff_time = $endtime - $startime; return array('diff_time'= $diff_time, 'return'= $res, 'header'= $header //计算当前时间 function getmicrotime() { list($usec, $sec) = explode(" ",microtime()); return ((float)$usec + (float)$sec); //测试一下，curl 三个网址 $array = array( "http://www.weibo.com/", "http://www.renren.com/", "http://www.qq.com/" $data = Curl_http($array,'10');//调用 var_dump($data);//输出//如果POST的数据大于1024字节，curl并不会直接就发起POST请求//发送请求时，header中包含一个空的Expect。curl_setopt($ch, CURLOPT_HTTPHEADER, array("Expect:"));我们再来看几个例子（1）下面这段代码是实现抓取多个URL，然后将抓取的URL的页面代码写入指定的文件$urls = array('http://www.phpstudy.net/','http://www.google.com/','http://www.example.com/'); // 设置要抓取的页面URL$save_to='/test.txt'; // 把抓取的代码写入该文件$st = fopen($save_to,"a");$mh = curl_multi_init();foreach ($urls as $i = $url) {$conn[$i] = curl_init($url);curl_setopt($conn[$i], CURLOPT_USERAGENT, "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)");curl_setopt($conn[$i], CURLOPT_HEADER ,0);curl_setopt($conn[$i], CURLOPT_CONNECTTIMEOUT,60);curl_setopt($conn[$i], CURLOPT_FILE,$st); // 将爬取的代码写入文件curl_multi_add_handle ($mh,$conn[$i]);} // 初始化curl_multi_exec($mh,$active);} while ($active); // 执行foreach ($urls as $i = $url) {curl_multi_remove_handle($mh,$conn[$i]);curl_close($conn[$i]);} // 结束清理curl_multi_close($mh);fclose($st);（2）下面这段代码和上面差不多意思，只不过这个地方是将获得的代码先放入变量，然后再将获取到的内容写入指定的文件$urls = array('http://www.phpstudy.net/','http://www.google.com/','http://www.example.com/'$save_to='/test.txt'; // 把抓取的代码写入该文件$st = fopen($save_to,"a");$mh = curl_multi_init();foreach ($urls as $i = $url) {$conn[$i] = curl_init($url);curl_setopt($conn[$i], CURLOPT_USERAGENT, "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.0)");curl_setopt($conn[$i], CURLOPT_HEADER ,0);curl_setopt($conn[$i], CURLOPT_CONNECTTIMEOUT,60);curl_setopt($conn[$i],CURLOPT_RETURNTRANSFER,true); // 不将爬取代码写到浏览器，而是转化为字符串curl_multi_add_handle ($mh,$conn[$i]);curl_multi_exec($mh,$active);} while ($active);foreach ($urls as $i = $url) {$data = curl_multi_getcontent($conn[$i]); // 获得爬取的代码字符串fwrite($st,$data); // 将字符串写入文件} // 获得数据变量，并写入文件foreach ($urls as $i = $url) {curl_multi_remove_handle($mh,$conn[$i]);curl_close($conn[$i]);curl_multi_close($mh);fclose($st);（3）下面这段代码实现的是利用 PHP 的 Curl Functions 实现并发多线程下载文件$urls=array( 'http://www.phpstudy.net/5w.zip', 'http://www.phpstudy.net/5w.zip', 'http://www.phpstudy.net/5w.zip'$save_to='./home/';$mh=curl_multi_init();foreach($urls as $i= $url){ $g=$save_to.basename($url); if(!is_file($g)){ $conn[$i]=curl_init($url); $fp[$i]=fopen($g,"w"); curl_setopt($conn[$i],CURLOPT_USERAGENT,"Mozilla/4.0(compatible; MSIE 7.0; Windows NT 6.0)"); curl_setopt($conn[$i],CURLOPT_FILE,$fp[$i]); curl_setopt($conn[$i],CURLOPT_HEADER ,0); curl_setopt($conn[$i],CURLOPT_CONNECTTIMEOUT,60); curl_multi_add_handle($mh,$conn[$i]); $n=curl_multi_exec($mh,$active);}while($active);foreach($urls as $i= $url){ curl_multi_remove_handle($mh,$conn[$i]); curl_close($conn[$i]); fclose($fp[$i]);curl_multi_close($mh);$urls=array( 'http://www.phpstudy.net/5w.zip', 'http://www.phpstudy.net/5w.zip', 'http://www.phpstudy.net/5w.zip'$save_to='./home/';$mh=curl_multi_init();foreach($urls as $i= $url){ $g=$save_to.basename($url); if(!is_file($g)){ $conn[$i]=curl_init($url); $fp[$i]=fopen($g,"w"); curl_setopt($conn[$i],CURLOPT_USERAGENT,"Mozilla/4.0(compatible; MSIE 7.0; Windows NT 6.0)"); curl_setopt($conn[$i],CURLOPT_FILE,$fp[$i]); curl_setopt($conn[$i],CURLOPT_HEADER ,0); curl_setopt($conn[$i],CURLOPT_CONNECTTIMEOUT,60); curl_multi_add_handle($mh,$conn[$i]); $n=curl_multi_exec($mh,$active);}while($active);foreach($urls as $i= $url){ curl_multi_remove_handle($mh,$conn[$i]); curl_close($conn[$i]); fclose($fp[$i]);curl_multi_close($mh);以上所述就是本文的全部内容了，希望大家能够喜欢。PHP教程

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