http request encapsulation class written in php

<?php
    /**
     *  HTTP常用请求封装
     * @version $Id: HttpHelper.php,v 1.0 2012-8-9
     * @package library
     * @site bbs.it-home.org
     */

    // ---------------------------

    /**
     * http请求处理
     *
     * 开发中经常需要模拟提交请求，本类封装了常用的post方法
     *
     * @author ustb80
     *
     */
    class HttpHelper
    {
        // 当前的user-agent字符串
        public $ua_string= "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.7; rv:14.0) Gecko/20100101 Firefox/14.0.1";

        // 支持的提交方式
        public $post_type_list = array("curl", "socket", "stream");

        // 本地cookie文件
        private $cookie_file;

        // -----------------------

        /**
         * 构造函数
         *
         * @param array $params 初始化参数
         */
        public function __construct($params = array())
        {
            if(count($params) > 0)
            {
                $this->init($params);
            }
        }

        // -----------------------

        /**
         * 参数初始化
         *
         * @param array $params
         */
        public function init($params)
        {
            if(count($params) > 0)
            {
                foreach($params as $key => $val)
                {
                    if(isset($this->$key))
                    {
                        $this->$key = $val;
                    }
                }
            }
        }

        // -----------------------

        /**
         * 提交请求
         *
         * @param string $url 请求地址
         * @param mixed $data 提交的数据
         * @param string $type 提交类型，curl,socket,stream可选
         */
        public function post($url, $data, $type = "socket")
        {
            if(!in_array($type, $this->post_type_list))
            {
                die("undefined post type");
            }
            $function_name = $type . "Post";
            return call_user_func_array(array($this, $function_name), array($url, $data));
        }

        // -----------------------

        /**
         * 更改默认的ua信息
         *
         * 本方法常用于模拟各种浏览器
         *
         * @param string $ua_string UA字符串
         */
        public function setUA($user_agent)
        {
            $this->ua_string = $user_agent;
            return $this;
        }

        // -----------------------

        /**
         * 设置本地cookie文件
         *
         * 在用curl来模拟时常需要设置此项
         *
         * @param string $cookie_file 文件路径
         */
        public function setCookieFile($cookie_file)
        {
            $this->cookie_file = $cookie_file;
            return $this;
        }

        // -----------------------

        /**
         * curl方式提交
         *
         * @param string $url 请求地址
         * @param mixed $data 提交的数据
         * @param string $user_agent 自定义的UA
         * @return mixed
         */
        public function curlPost($url, $data, $user_agent = '')
        {
            if($user_agent == '')
            {
                $user_agent = $this->ua_string;
            }

            if (!is_array($data))
            {
                $data = array($data);
            }

            $data = http_build_query($data);

            if (!function_exists("curl_init"))
            {
                die('undefined function curl_init');
            }

            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $url);
            curl_setopt($ch, CURLOPT_POST, true);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_USERAGENT, $user_agent);
            $rs = curl_exec($ch);
            curl_close($ch);
            return $rs;
        }

        // -----------------------

        /**
         * 套接字提交
         *
         * @param string $url 请求地址
         * @param mixed $data 提交的数据
         * @param string $user_agent 自定义的UA
         * @param int $port 端口
         * @param int $timeout 超时限制
         * @return mixed
         */
        public function socketPost($url, $data, $user_agent = '', $port = 80, $timeout = 30)
        {
            $url_info = parse_url($url);
            $remote_server = $url_info['host'];
            $remote_path = $url_info['path'];
            $socket = fsockopen($remote_server, $port, $errno, $errstr, $timeout);
            if(!$socket)
            {
                die("$errstr($errno)");
            }

            if($user_agent == '')
            {
                $user_agent = $this->ua_string;
            }

            if (!is_array($data))
            {
                $data = array($data);
            }

            $data = http_build_query($data);

            fwrite($socket, "POST {$remote_path} HTTP/1.0\r\n");
            fwrite($socket, "User-Agent: {$user_agent}\r\n");
            fwrite($socket, "HOST: {$remote_server}\r\n");
            fwrite($socket, "Content-type: application/x-www-form-urlencoded\r\n");
            fwrite($socket, "Content-length: " . strlen($data) . "\r\n");
            fwrite($socket, "Accept:*/*\r\n");
            fwrite($socket, "\r\n");
            fwrite($socket, "{$data}\r\n");
            fwrite($socket, "\r\n");

            $header = "";
            while($str = trim(fgets($socket, 4096)))
            {
                $header .= $str;
            }

            $data = "";
            while(!feof($socket))
            {
                $data .= fgets($socket, 4096);
            }

            return $data;
        }

        // -----------------------

        /**
         * 文件流提交
         *
         * @param string $url 提交地址
         * @param string $data 数据
         * @param string $user_agent 自定义的UA
         * @return mixed
         */
        public function streamPost($url, $data, $user_agent = '')
        {
            if($user_agent == '')
            {
                $user_agent = $this->ua_string;
            }

            if (!is_array($data))
            {
                $data = array($data);
            }

            $data = http_build_query($data);
            $context = array(
                    'http' => array(
                            'method' => 'POST',
                            'header' => 'Content-type: application/x-www-form-urlencoded'
 . "\r\n" . 'User-Agent : ' . $user_agent . "\r\n" . 'Content-length: ' . strlen($data),
                            'content' => $data
                    )
            );
            $stream_context = stream_context_create($context);
            $data = file_get_contents($url, FALSE, $stream_context);
            return $data;
        }

        // -----------------------

        /**
         * 发送请求
         *
         * 本方法通过curl函数向目标服务器发送请求
         *
         * @param string $url 请求地址
         * @return mixed
         */
        public function request($url)
        {
            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $url);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
            curl_setopt($ch, CURLOPT_USERAGENT, !empty($this->ua_string)? $this->ua_string : $_SERVER['HTTP_USER_AGENT']);
            curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);

            if (isset($this->cookie_file))
            {
                curl_setopt($ch, CURLOPT_COOKIEJAR, $this->cookie_file);
            }
            $data = curl_exec($ch);
            curl_close($ch);

            return $data;
        }
    }
?>

<?php
    require_once 'HttpHelper.php';
    $HttpHelper = new HttpHelper();

    $url = "http://localhost/post.php";

    $data = array("name"=>"socket");
    $rs[] = $HttpHelper->post($url, $data);

    $data = array("name"=>"curl");
    $rs[] = $HttpHelper->post($url, $data, "curl");

    $data = array("name"=>"stream");
    $rs[] = $HttpHelper->post($url, $data, "stream");

    $rs[] = $HttpHelper->request($url);

    print_r($rs);
?>

<?php
    echo 'test request:';
    print_r($_REQUEST);
?>