private void SelectAll()
    {
        //新程式
        string SessionIDName = string.Format("{0}_{1}", PAGE_DT_01, PageTimeStamp.Value);
        ErrorMsgLabel.Text = "";
        try
        {
            VGRModel.MaintainReturnData BCOIVM = new VGRModel.MaintainReturnData(ConnectionDB);
            dtClassAndItemSelected = BCOIVM.GetStockByVendor(Vendor, SLP_RootNo.Text, LocateSection);
            Session[SessionIDName] = dtClassAndItemSelected;
            GridView1.DataSource = dtClassAndItemSelected;
            GridView1.PageSize = 20;
            //GridView1.PageSize = (TextBoxPagesize.Text == "") ? 10 : (int.Parse(TextBoxPagesize.Text) < 0) ? 10 : int.Parse(TextBoxPagesize.Text);
            GridView1.PageIndex = 0;
            GridView1.DataBind();
            GridView1.SelectedIndex = -1;

            if (dtClassAndItemSelected == null || (dtClassAndItemSelected != null && dtClassAndItemSelected.Rows.Count <= 0))
            {
                ScriptManager.RegisterStartupScript(UpdatePanel1, this.GetType(), "ClientScript", "alert('查無資料');", true);
                return;
            }

            for (int i = 0; i < GridView1.Rows.Count; i++)
            {
                CheckBox chk_Sgl = (CheckBox)GridView1.Rows[i].FindControl("chk_Sgl");
                chk_Sgl.Checked = true;
            }

            CheckBox chbAll = (CheckBox)GridView1.HeaderRow.FindControl("chbAll");
            chbAll.Checked = true;
        }
        catch (Exception ex)
        {
            ErrorMsgLabel.Text = ex.ToString();
        }
    }