protected void Button1_Click(object sender, EventArgs e)
        {
            DDL.Focus();
            int tempqnty  = Convert.ToInt32(qntyTxt.Text);
            int tempStock = Convert.ToInt32(ViewState["tempStock"]);

            if (qntyTxt.Text != "" && tempqnty <= tempStock && availTxt.Text != "" && priceTxt.Text != "" && discTxt.Text != "" && Convert.ToInt32(availTxt.Text) != 0)
            {
                dt.Columns.Add("Sr#");
                dt.Columns.Add("Id");
                dt.Columns.Add("Item");
                dt.Columns.Add("Qnty");
                dt.Columns.Add("Rt");

                dt.Columns.Add("Price");
                DataRow dr = null;

                if (GridView1.Rows.Count == 0)
                {
                    ViewState["emp"] = null;
                }

                if (ViewState["emp"] != null)
                {
                    for (int i = 0; i < 1; i++)
                    {
                        dt = (DataTable)ViewState["emp"];
                        if (dt.Rows.Count > 0)
                        {
                            dr         = dt.NewRow();
                            dr["Sr#"]  = dt.Rows.Count + 1;;
                            dr["Id"]   = DDL.SelectedItem.Value;
                            dr["Item"] = DDL.SelectedItem.Text;
                            dr["Qnty"] = qntyTxt.Text;
                            dr["Rt"]   = priceTxt.Text;

                            dr["Price"] = Label1.Text;
                            dt.Rows.Add(dr);
                            GridView1.DataSource = dt;
                            GridView1.DataBind();
                        }
                    }
                }
                else
                {
                    dr          = dt.NewRow();
                    dr["Sr#"]   = dt.Rows.Count + 1;;
                    dr["Id"]    = DDL.SelectedItem.Value;
                    dr["Item"]  = DDL.SelectedItem.Text;
                    dr["Qnty"]  = qntyTxt.Text;
                    dr["Rt"]    = priceTxt.Text;
                    dr["Price"] = Label1.Text;
                    dt.Rows.Add(dr);
                    GridView1.DataSource = dt;
                    GridView1.DataBind();
                }
                ViewState["emp"] = dt;
                updated_grandTotal();
                // ViewState["gt"] = Convert.ToInt32(ViewState["gt"]) + Convert.ToInt32(Label1.Text);
                // grandTotal = grandTotal + Convert.ToInt32(Label1.Text);
                Label2.Text = "G-Total :" + ViewState["gt"].ToString();

                reset_item_btn();

                Asucc.Visible = true;
            }
            else
            {
                Asucc.Visible = false;
                Afail.Visible = true;
            }
        }