dedecms图片上传函数

/**
 * 图片上传类  
 * @param $file上传图片信息
 * @param $ty 
 */

function upload_pic($file, $ty) {
    if (!is_uploaded_file($file["tmp_name"])) {//是否存在文件
        tcmc::ShowMsg("图片不存在!", "turntable_index.php?op=index");
    }
    if (!in_array($file["type"], array('image/jpg', 'image/jpeg', 'image/png'))) {//检查文件类型
        tcmc::ShowMsg("文件类型不符！", "turntable_index.php?op=index");
    }
    $destination_folder = CMS_ROOT . 'uploads/miaosha/';
    if (!file_exists($destination_folder)) {
        mkdir($destination_folder);
    }
    $pinfo = pathinfo($file["name"]);
    $ftype = $pinfo['extension'];
    $destination = $destination_folder . "turntable_" . $ty . time() . "." . $ftype;
    $filename = $file["tmp_name"];
    if (file_exists($destination) && $overwrite != true) {
        tcmc::ShowMsg("同名文件已经存在了！", "turntable_index.php?op=index");
    }
    if (!move_uploaded_file($filename, $destination)) {
        tcmc::ShowMsg("移动文件出错1！", "turntable_index.php?op=index");
    }

    $len = strlen(CMS_ROOT);
    $subdestination = substr($destination, $len - );
    return $subdestination;
}