socket编程发送GET请求

可以根据几根url地址，分析出主机，地址，协议等，然后用封装成的类拼接成GET请求信息，用fsockopen连接主机，进行读取操作，获取响应信息，打印

<?php
//http连接接口
interface proto{
    //连接url
    public function conn($url);
    //发送get请求
    public function get();
    //发送post
    public function post($num);
    //关闭连接
    public function close();
}
class Http implements proto{
    const CRLF="\r\n";
    protected $response='';
    protected $poststr='';
    protected $errno=-1;
    protected $errstr='';
    protected $version='HTTP/1.1';
    protected $fh=null;
    protected $url=array();
    protected $line=array();
    protected $header=array();
    protected $body=array();

    public function __construct($url){
        $this->conn($url);
        $this->setheader();
    }
    //负责写请求行
    protected function setLine($method){
        $this->line[0]=$method .' '.$this->url['path'] .' '.$this->version;
    }
    //负责写请求信息
    protected function setHeader(){
        $this->header[]='Host:'.$this->url['host'];
    }
    //负责写主题信息
    protected function setBody($body){
        $this->body=array(http_build_query($body));
    }

    //连接url
    public function conn($url){
        $this->url=parse_url($url);
        //判断端口
        if(!isset($this->url['port'])){
            $this->url['port']=80;
        }
        $this->fh=fsockopen($this->url['host'],$this->url['port'],$this->errno,$this->errstr,3);
    }
    //构造get请求数据
    public function get(){
        $this->setLine('GET');
        $this->request();
        return $this->response;
    }
    //构造post请求数据
    public function post($body=array()){
        $this->setLine('POST');

        $this->header[]='content-type:application/x-www-form-urlencoded';
        // print_r($this->header);
        $this->setBody($body);
        $this->header[]='content-length:'.strlen($this->body[0]);
        $this->request();
        return $this->response;
    }

    //真正的请求
    public function request(){
        $req=array_merge($this->line,$this->header,array(''),$this->body,array(''));//拼接请求信息为数组
        // print_r($req);
        $req=implode(self::CRLF,$req);
        //echo $req;exit();
        fwrite($this->fh,$req);

        while(!feof($this->fh)){
            $this->response.=fread($this->fh,1024);
        }
        $this->close();

    }
    //关闭连接
    public function close(){
        fclose($this->fh);
    }

}

//调试
$url='http://localhost/tieba/cunchu.php';
$http=new Http($url);
// echo $http->get();
// print_r($http);
echo $http->post(array('username'=>'zhangsan','title'=>'试试发帖','content'=>'这是用http协议拼接数据发送的'));
?>