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;     }}