php网络爬虫技术

function get_urls($url){  

       $url_array=array();  

       $the_first_content=file_get_contents($url);  

       $the_second_content=file_get_contents($url);  

       $pattern1 = "/http:\/\/[a-zA-Z0-9\.\?\/\-\=\&\:\+\-\_\'\"]+/";  

       $pattern2="/http:\/\/[a-zA-Z0-9\.]+/";  

       preg_match_all($pattern2, $the_second_content, $matches2);  

       preg_match_all($pattern1, $the_first_content, $matches1);  

       $new_array1=array_unique($matches1[0]);  

       $new_array2=array_unique($matches2[0]);  

       $final_array=array_merge($new_array1,$new_array2);  

       $final_array=array_unique($final_array);  

       for($i=0;$i<count($final_array);$i++)  

       {  

          echo $final_array[$i]."<br/>";  

       }  

   }  

    get_urls("http://www.baidu.com");