asp.net上传文件

#region 上传文件的方法
    /// <summary>
    /// 上传文件方法
    /// </summary>
    /// <param name="myFileUpload">上传控件ID</param>
    /// <param name="allowExtensions">允许上传的扩展文件名类型,如：string[] allowExtensions = { ".doc", ".xls", ".ppt", ".jpg", ".gif" };</param>
    /// <param name="maxLength">允许上传的最大大小，以M为单位</param>
    /// <param name="savePath">保存文件的目录，注意是绝对路径,如：Server.MapPath("~/upload/");</param>
    /// <param name="saveName">保存的文件名，如果是""则以原文件名保存</param>
    private void Upload(FileUpload myFileUpload, string[] allowExtensions, int maxLength, string savePath, string saveName)
    {
        // 文件格式是否允许上传
        bool fileAllow = false;

        //检查是否有文件案
        if (myFileUpload.HasFile)
        {
            // 检查文件大小, ContentLength获取的是字节，转成M的时候要除以2次1024
            if (myFileUpload.PostedFile.ContentLength / 1024 / 1024 >= maxLength)
            {
                throw new Exception("只能上传小于2M的文件！");
            }

            //取得上传文件之扩展文件名，并转换成小写字母
            string fileExtension = System.IO.Path.GetExtension(myFileUpload.FileName).ToLower();
            string tmp = "";   // 存储允许上传的文件后缀名
            //检查扩展文件名是否符合限定类型
            for (int i = 0; i < allowExtensions.Length; i++)
            {
                tmp += i == allowExtensions.Length - 1 ? allowExtensions[i] : allowExtensions[i] + ",";
                if (fileExtension == allowExtensions[i])
                {
                    fileAllow = true;
                }
            }

            if (fileAllow)
            {
                try
                {
                    string path = savePath + (saveName == "" ? myFileUpload.FileName : saveName);
                    //存储文件到文件夹
                    myFileUpload.SaveAs(path);
                }
                catch (Exception ex)
                {
                    throw new Exception(ex.Message);
                }
            }
            else
            {
                throw new Exception("文件格式不符，可以上传的文件格式为：" + tmp);
            }
        }
        else
        {
            throw new Exception("请选择要上传的文件！");
        }
    }
    #endregion


以下是测试的代码：
        try
        {
            string[] ss = { ".jpg", ".gif" };
            string path = Request.MapPath("~/upload/");
            Upload(FileUpload1, ss, 1, path, "");
            Label1.Text = "文件上传成功！";
        }
        catch (Exception ex)
        {
            Label1.Text = ex.Message;
        }