PHP模擬POST請求

/**
    *
    * @param $url
    * @param $data
    * @return string
    */
   public static function request_post($url, $data){//file_get_content
       $postdata = http_build_query(
           $data

       );

       $opts = array('http' =>
           array(
               'method'  => 'POST',
               'header'  => 'Content-type: application/x-www-form-urlencoded',
               'content' => $postdata
           )

       );

       $context = stream_context_create($opts);
       $result = file_get_contents($url, false, $context);
       return $result;
   }