php結(jié)合curl實(shí)現(xiàn)多線程抓取

<&#63;php
/*
curl 多線程抓取
*/
 /** 
   * curl 多線程 
   * 
   * @param array $array 并行網(wǎng)址 
   * @param int $timeout 超時(shí)時(shí)間
   * @return array 
   */ 
 function Curl_http($array,$timeout){
 $res = array();
 $mh = curl_multi_init();//創(chuàng)建多個(gè)curl語(yǔ)柄
 $startime = getmicrotime();
 foreach($array as $k=>$url){
  $conn[$k]=curl_init($url);

    curl_setopt($conn[$k], CURLOPT_TIMEOUT, $timeout);//設(shè)置超時(shí)時(shí)間
    curl_setopt($conn[$k], CURLOPT_USERAGENT, 'Mozilla/5.0 (compatible; MSIE 5.01; Windows NT 5.0)');
    curl_setopt($conn[$k], CURLOPT_MAXREDIRS, 7);//HTTp定向級(jí)別
    curl_setopt($conn[$k], CURLOPT_HEADER, 0);//這里不要header，加塊效率
    curl_setopt($conn[$k], CURLOPT_FOLLOWLOCATION, 1); // 302 redirect
    curl_setopt($conn[$k],CURLOPT_RETURNTRANSFER,1);
    curl_multi_add_handle ($mh,$conn[$k]);
 }
 //防止死循環(huán)耗死cpu 這段是根據(jù)網(wǎng)上的寫法
 do {
  $mrc = curl_multi_exec($mh,$active);//當(dāng)無(wú)數(shù)據(jù)，active=true
 } while ($mrc == CURLM_CALL_MULTI_PERFORM);//當(dāng)正在接受數(shù)據(jù)時(shí)
 while ($active and $mrc == CURLM_OK) {//當(dāng)無(wú)數(shù)據(jù)時(shí)或請(qǐng)求暫停時(shí)，active=true
  if (curl_multi_select($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]);//獲得返回信息
    $header[$k]=curl_getinfo($conn[$k]);//返回頭信息
    curl_close($conn[$k]);//關(guān)閉語(yǔ)柄
    curl_multi_remove_handle($mh , $conn[$k]);  //釋放資源 
 }

 curl_multi_close($mh);
 $endtime = getmicrotime();
 $diff_time = $endtime - $startime;

 return array('diff_time'=>$diff_time,
   'return'=>$res,
   'header'=>$header 
   );

 }
 //計(jì)算當(dāng)前時(shí)間
 function getmicrotime() {
   list($usec, $sec) = explode(" ",microtime());
   return ((float)$usec + (float)$sec);
 }

 //測(cè)試一下，curl 三個(gè)網(wǎng)址
 $array = array(
  "http://www.weibo.com/",
  "http://www.renren.com/",
  "http://www.qq.com/"
  );
 $data = Curl_http($array,'10');//調(diào)用
 var_dump($data);//輸出
//如果POST的數(shù)據(jù)大于1024字節(jié)，curl并不會(huì)直接就發(fā)起POST請(qǐng)求
//發(fā)送請(qǐng)求時(shí)，header中包含一個(gè)空的Expect。curl_setopt($ch, CURLOPT_HTTPHEADER, array("Expect:"));
&#63;>

我們?cè)賮?lái)看幾個(gè)例子

（1）下面這段代碼是實(shí)現(xiàn)抓取多個(gè)URL，然后將抓取的URL的頁(yè)面代碼寫入指定的文件

$urls = array(
'http://www.bitsCN.com/',
'http://www.google.com/',
'http://www.example.com/'
); // 設(shè)置要抓取的頁(yè)面URL
$save_to='/test.txt'; // 把抓取的代碼寫入該文件
$st = fopen($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); // 將爬取的代碼寫入文件
curl_multi_add_handle ($mh,$conn[$i]);
} // 初始化
do {
curl_multi_exec($mh,$active);
} while ($active); // 執(zhí)行
foreach ($urls as $i => $url) {
curl_multi_remove_handle($mh,$conn[$i]);
curl_close($conn[$i]);
} // 結(jié)束清理
curl_multi_close($mh);
fclose($st);

（2）下面這段代碼和上面差不多意思，只不過(guò)這個(gè)地方是將獲得的代碼先放入變量，然后再將獲取到的內(nèi)容寫入指定的文件

$urls = array(
'http://www.bitsCN.com/',
'http://www.google.com/',
'http://www.example.com/'
);
$save_to='/test.txt'; // 把抓取的代碼寫入該文件
$st = fopen($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[$i],CURLOPT_RETURNTRANSFER,true); // 不將爬取代碼寫到瀏覽器，而是轉(zhuǎn)化為字符串
curl_multi_add_handle ($mh,$conn[$i]);
}
do {
curl_multi_exec($mh,$active);
} while ($active);
foreach ($urls as $i => $url) {
$data = curl_multi_getcontent($conn[$i]); // 獲得爬取的代碼字符串
fwrite($st,$data); // 將字符串寫入文件
} // 獲得數(shù)據(jù)變量，并寫入文件
foreach ($urls as $i => $url) {
curl_multi_remove_handle($mh,$conn[$i]);
curl_close($conn[$i]);
}
curl_multi_close($mh);
fclose($st);

（3）下面這段代碼實(shí)現(xiàn)的是利用 PHP 的 Curl Functions 實(shí)現(xiàn)并發(fā)多線程下載文件

$urls=array(
 'http://www.bitsCN.com/5w.zip',
 'http://www.bitsCN.com/5w.zip',
 'http://www.bitsCN.com/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]);
 }
}
do{
 $n=curl_multi_exec($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.bitsCN.com/5w.zip',
 'http://www.bitsCN.com/5w.zip',
 'http://www.bitsCN.com/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]);
 }
}
do{
 $n=curl_multi_exec($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?jī)?nèi)容了，希望大家能夠喜歡。