PHP上传文件（学习）

<?phpif (isset($_FILES['upfile'])){	if (is_uploaded_file($_FILES['upfile']['tmp_name'])){$upfile=$_FILES["upfile"];$name = $upfile["name"];$type = $upfile["type"];$size = $upfile["size"];$tmp_name = $upfile["tmp_name"];$error = $upfile["error"];$ok=0;switch($type){	case 'image/pjpeg':	$ok=1;	break;	case 'image/jpeg':	$ok=1;	break;	case 'image/gif':	$ok=1;	break;	case 'image/png':	$ok=1;	break;}if($ok==1&&$error=='0'){	if(move_uploaded_file($tmp_name,'up/'.$name)){	echo "上传成功！";}}else{	echo "上传失败，请检查格式";};}}?>