.NET upload image

http://topic.csdn.net/u/20080420/14/50667eb1-3066-46a7-b83d-49c3c81b8819.html

/ <summary>
    /// 上传图片
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void btnUpLoad_Click(object sender, EventArgs e)
    {
        try
        {
            string test = Server.MapPath("ImageFiles/" + DateTime.Now.ToString("yyyy-MM-dd"));  //用来生成文件夹
            if (!Directory.Exists(test))
            {
                Directory.CreateDirectory(test);
            }
            if (FileUpload1.PostedFile.FileName != "")
            {
               string  imgname = FileUpload1.PostedFile.FileName;
               string imgType = imgname.Substring(imgname.LastIndexOf(".") + 1);
            [color=#FF0000]   string quanname =DateTime.Now.ToString("yyyyMMddHHmmss")+imgname.LastIndexOf("\\")+"."+imgType ;[/color]   //这里是生成不同名字  
         if ("gif" != imgType && "jpg" != imgType && "GIF" != imgType && "JPG" != imgType)
                {
                    Response.Write("<script>alert('请选择gif,jpg格式的文件!');</script>");
                    return;
                }
        
                string imgurl = "ImageFiles/" + DateTime.Now.ToString("yyyy-MM-dd") + "/" + quanname;//保存到数据库中是imgurl
                 FileUpload1.PostedFile.SaveAs(Server.MapPath(imgurl));
                       
 }
            else
            {
                Response.Write("<script>alert('请选择文件上传!');</script>");
            }
        }

        catch (Exception ex)
        {
            throw ex;
        }
    }