本文实例分析了PHP多线程之内部多线程用法。分享给大家供大家参考。具体如下：

复制代码 代码如下:<?phpclass Http_MultiRequest{    //要并行抓取的url 列表    private $urls = array();    //curl 的选项    private $options;    //构造函数    function __construct($options = array())    {        $this->setOptions($options);    }    //设置url 列表    function setUrls($urls)    {        $this->urls = $urls;        return $this;    }    //设置选项    function setOptions($options)    {        $options[CURLOPT_RETURNTRANSFER] = 1;        if (isset($options["HTTP_POST"]))         {            curl_setopt($ch, CURLOPT_POST, 1);            curl_setopt($ch, CURLOPT_POSTFIELDS, $options["HTTP_POST"]);            unset($options["HTTP_POST"]);        }        if (!isset($options[CURLOPT_USERAGENT]))         {            $options[CURLOPT_USERAGENT] = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1;)";        }        if (!isset($options[CURLOPT_FOLLOWLOCATION]))         {            $options[CURLOPT_FOLLOWLOCATION] = 1;        }        if (!isset($options[CURLOPT_HEADER]))        {            $options[CURLOPT_HEADER] = 0;        }        $this->options = $options;    }    //并行抓取所有的内容    function exec()    {        if(empty($this->urls) || !is_array($this->urls))        {            return false;        }        $curl = $data = array();        $mh = curl_multi_init();        foreach($this->urls as $k => $v)        {            $curl[$k] = $this->addHandle($mh, $v);        }        $this->execMulitHandle($mh);        foreach($this->urls as $k => $v)        {            $data[$k] = curl_multi_getcontent($curl[$k]);            curl_multi_remove_handle($mh, $curl[$k]);        }        curl_multi_close($mh);        return $data;    }    //只抓取一个网页的内容。    function execOne($url)    {        if (empty($url)) {            return false;        }        $ch = curl_init($url);        $this->setOneOption($ch);        $content = curl_exec($ch);        curl_close($ch);        return $content;    }    //内部函数，设置某个handle 的选项    private function setOneOption($ch)    {        curl_setopt_array($ch, $this->options);    }    //添加一个新的并行抓取 handle    private function addHandle($mh, $url)    {        $ch = curl_init($url);        $this->setOneOption($ch);        curl_multi_add_handle($mh, $ch);        return $ch;    }    //并行执行(这样的写法是一个常见的错误，我这里还是采用这样的写法，这个写法    //下载一个小文件都可能导致cup占用100%, 并且，这个循环会运行10万次以上    //这是一个典型的不懂原理产生的错误。这个错误在PHP官方的文档上都相当的常见。）    private function execMulitHandle($mh)    {        $running = null;        do {            curl_multi_exec($mh, $running);        } while ($running > 0);    }}/*下面是上面的类的一个测试的例子：*/$urls = array("http://baidu.com", "http://baidu.com", "http://baidu.com", "http://baidu.com", "http://baidu.com", "http://baidu.com", "http://www.google.com", "http://www.sina.com.cn", );$m = new Http_MultiRequest();$t = microtime(true);$m->setUrls($urls);//parallel fetch（并行抓取）:$data = $m->exec();$parallel_time = microtime(true) - $t;echo $parallel_time . "";$t = microtime(true);//serial fetch（串行抓取）:foreach ($urls as $url){    $data[] = $m->execOne($url);}$serial_time = microtime(true) - $t;echo $serial_time . "";

希望本文所述对大家的php程序设计有所帮助。