php模拟post数据，图片

1.fsockopen方式，可post图片：//例子：socket_post('http://site.com/', array('key1'=>'value1', 'key2'=>'value2'), array('filekey'=>'filepath'))    function socket_post($url, $postdata=array(), $files=array())    {        $boundary = '-------'.substr(md5(rand(0,32000)),0,10);        $encoded = "";        if($postdata){            while(list($k,$v) = each($postdata)){                $encoded .= "--$boundary\r\nContent-Disposition: form-data; name=\"".rawurlencode($k)."\"\r\n\r\n";                $encoded .= rawurlencode($v)."\r\n";            }        }        if($files){            foreach($files as $name=>$file){                $ext= strtolower(strrchr($file,"."));                switch($ext){                    case '.gif':                        $type = "image/gif";                        break;                    case '.jpg':                        $type = "image/jpeg";                        break;                    case '.png':                        $type = "image/png";                        break;                    default:                        $type = "image/jpeg";                }                $encoded .= "--$boundary\r\nContent-Disposition: form-data; name=\"".rawurlencode($name)."\"; filename=\"$file\"\r\nContent-Type: $type\r\n\r\n";                $encoded .= join("", file($file));                $encoded .= "\r\n";            }        }        $encoded .= "--$boundary--\r\n";        $length = strlen($encoded);                $uri = parse_url($url);        $fp = fsockopen($uri['host'], $uri['port'] ? $uri['port'] : 80);        if(!$fp)            return "Failed to open socket to ".$uri['host'];                fputs($fp, sprintf("POST %s%s%s HTTP/1.0\r\n", $uri['path'], $uri['query'] ? "?" : "", $uri['query']));        fputs($fp, "Host: ".$uri['host']."\r\n");        fputs($fp, "Content-type: multipart/form-data; boundary=$boundary\r\n");        fputs($fp, "Content-length: $length\r\n");        fputs($fp, "Connection: close\r\n\r\n");        fputs($fp, $encoded);                $results = "";        while(!feof($fp)){            $results .= fgets($fp,1024);        }        fclose($fp);        return preg_replace('/^HTTP(.*?)\r\n\r\n/s','',$results);    }2.file_get_contents方式，不能post文件：function Post($url, $post = null) { $context = array(); if (is_array($post)) { ksort($post); $context['http'] = array ( 'method' => 'POST', 'header'=>'Content-type: application/x-www-form-urlencoded','content' => http_build_query($post, '', '&'), ); } return file_get_contents($url, false, stream_context_create($context)); }