asp:FileUpload 上次图片

 <asp:FileUpload ID="FileUpload附件" runat="server" Width="200px" />protected void btnEdit_Click(object sender, EventArgs e)
        {
            if (txtCarPlateNumber.Text.Trim() == "")
            {
                ClientScript.RegisterStartupScript(GetType(), "", "alert('请输入车牌号！');", true);
                return;
            }
            int Id = 0;
            if (string.IsNullOrEmpty(Request.Params["Id"]) == false)
            {
                Id = int.Parse(Request.Params["Id"]);
            }
            ModelBlackWhiteList model = new ModelBlackWhiteList();
            model.Id = Id;
            model.CarPlateType = ddlCarPlateType.SelectedItem.Text;
            model.CarPlateNumber = txtCarPlateNumber.Text.Trim();
            model.Company = txtCompany.Text.Trim();
            model.BWFlag = ddlBWFlag.SelectedItem.Value;
            model.OperatorName = this.UserLogin;
            model.CreateDateTime = DateTime.Now;            string CommandName = Request.Params["CommandName"].ToString();
            switch (CommandName)
            {
                case "Upd":
                    {
                        if (FileUpload附件.PostedFile.FileName.Trim().Length != 0)
                        {
                            string savePath;
                            string fileName = DateTime.Now.ToString("yyyyMMddHHmmssms");
                            if (FileUpload附件.HasFile && FileUpload附件.PostedFile.FileName.Contains(".jpg"))
                            {
                                savePath = Server.MapPath("~/Upload/");//指定上传文件在服务器上的保存路径
                                                                       //检查服务器上是否存在这个物理路径，如果不存在则创建
                                if (!System.IO.Directory.Exists(savePath))
                                {
                                    System.IO.Directory.CreateDirectory(savePath);
                                }
                                savePath = savePath + fileName + ".jpg";
                                FileUpload附件.SaveAs(savePath);
                                model.CarPicPath = "/Upload /" + fileName + ".jpg";
                            }
                            else
                            {
                                ClientScript.RegisterStartupScript(GetType(), "", "alert('请选择JPG图片文件！');", true);
                                return;
                            }
                        }
                        int result = SqlSugarClientHelper.SqlDBConnection.Updateable<ModelBlackWhiteList>(model).ExecuteCommand();
                        if (result > 0)
                        {
                            ClientScript.RegisterStartupScript(GetType(), "", "alert('保存成功！');window.location = 'BlackWhiteListManage.aspx';", true);
                        }
                        else
                        {
                            ClientScript.RegisterStartupScript(GetType(), "", "alert('保存失败！');", true);
                        }
                        break;
                    }
                case "New":
                    {
                        if (FileUpload附件.PostedFile.FileName.Trim().Length != 0)
                        {
                            string savePath;
                            string fileName = DateTime.Now.ToString("yyyyMMddHHmmssms");
                            if (FileUpload附件.HasFile && FileUpload附件.PostedFile.FileName.Contains(".jpg"))
                            {
                                savePath = Server.MapPath("~/Upload/BWFLag/");//指定上传文件在服务器上的保存路径
                                                                              //检查服务器上是否存在这个物理路径，如果不存在则创建
                                if (!System.IO.Directory.Exists(savePath))
                                {
                                    System.IO.Directory.CreateDirectory(savePath);
                                }
                                savePath = savePath + fileName + ".jpg";
                                FileUpload附件.SaveAs(savePath);
                                model.CarPicPath = "/Upload/BWFLag/" + fileName + ".jpg";
                            }
                            else
                            {
                                ClientScript.RegisterStartupScript(GetType(), "", "alert('请选择JPG图片文件！');", true);
                                return;
                            }
                        }
                        int result = SqlSugarClientHelper.SqlDBConnection.Insertable<ModelBlackWhiteList>(model).ExecuteCommand();
                        if (result > 0)
                        {
                            ClientScript.RegisterStartupScript(GetType(), "", "alert('保存成功！');window.location = 'BlackWhiteListManage.aspx';", true);
                        }
                        else
                        {
                            ClientScript.RegisterStartupScript(GetType(), "", "alert('保存失败！');", true);
                        }
                        break;
                    }
            }
        }