php 多个文件上传

foreach($_files as $f)
{
 //处理中文名
 if (function_exists("iconv"))  $f[name] = iconv("utf-8","gb2312",$f[name]);

 $unm=intval(mt_rand(1000,9999));
 $file="z_upload/".date("ymdhms").$unm.$f[name];

 //检查是否已经存在同名文件
 if (file_exists($file))  header("http/1.0 403");
 //保存文件
 
 if (!@move_uploaded_file($f["tmp_name"],$file)) 
 {
 header("http/1.0 404 not found");
 }else{
 if(!isset($_cookie['uploadpic'])){
   setcookie("uploadpic",$file);
}else{
unlink($_cookie['uploadpic']);
setcookie("uploadpic","");
setcookie("uploadpic",$file);
}
 echo "1";
 
 }
}
?>