PHP发送POST请求的三种方式

<?php 
//PHP发送POST请求的三种方式 分别使用curl  file_get_content  fsocket 来实现post提交数据
class Request{
public static function post($url, $post_data = '', $timeout = 5){//curl
$ch = curl_init();
curl_setopt ($ch, CURLOPT_URL, $url);
        curl_setopt ($ch, CURLOPT_POST, 1);
        if($post_data != ''){
            curl_setopt($ch, CURLOPT_POSTFIELDS, $post_data);
        }
        curl_setopt ($ch, CURLOPT_RETURNTRANSFER, 1); 
        curl_setopt ($ch, CURLOPT_CONNECTTIMEOUT, $timeout);
        curl_setopt($ch, CURLOPT_HEADER, false);
        $file_contents = curl_exec($ch);
        curl_close($ch);
        return $file_contents;
    }

    public static function post2($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;
    }

    public static function post3($host,$path,$query,$others=''){//fsocket
        $post="POST $path HTTP/1.1\r\nHost: $host\r\n";
        $post.="Content-type: application/x-www-form-";
        $post.="urlencoded\r\n${others}";
        $post.="User-Agent: Mozilla 4.0\r\nContent-length: ";
        $post.=strlen($query)."\r\nConnection: close\r\n\r\n$query";
        $h=fsockopen($host,80);
        fwrite($h,$post);
        for($a=0,$r='';!$a;){
$b=fread($h,8192);
$r.=$b;
$a=(($b=='')?1:0);
}
fclose($h);
        return $r;
    }
}
?>