function uplond() {
            var oImg = document.getElementById("mainphoto");
            ImgUploadManger.imgView.uploadImg(location.protocol + '//' + location.host + "/", oImg.src, window.location.search, oImg.width, oImg.height);
            alert('下载成功、存放在D盘根目录下！');            
                    }

[AjaxPro.AjaxMethod]
        public void uploadImg(string _physicalApplicationPath, string _src, string _search, int _width, int _heigth)
        {
            //获取比例图的大小
            int width = _width;
            int height = _heigth;
            _src = _src.Replace(_physicalApplicationPath, "");
            //生成比例图
            Images img = new Images();
            string src = img.Thumbnail1(Server.MapPath("../") + _src, width, height);
            string filepath = src;
            string urlpath = src.Replace(Server.MapPath("../"), "");
            string filename = System.IO.Path.GetFileName(filepath);
            try
            {
             //这里是下载
                WebClient wc = new WebClient();
                wc.DownloadFile(_physicalApplicationPath + urlpath, "d:\\" + filename);
                wc.Dispose();                 
            }
            catch (Exception ex)
            {
                ClientScript.RegisterStartupScript(typeof(string), "Err", string.Format("<script language='javascript'>alert('{0}');</script>", ex.Message));
                return;
            }
            
        }