delete row ใน gridview แบบไม่ได้ delete จาก Database

protected void dgvOrder_RowDeleting(object sender, GridViewDeleteEventArgs e)
    {
        getDGVOrder();  // read gridview

        // ดึง key มาจาก กริดวิว
        string barcode = dgvOrder.DataKeys[e.RowIndex].Values.ToString(); 
        string cmd = ((Button)dgvOrder.Rows[e.RowIndex].FindControl("rowToDelete")).Text;
        
        // load data table  อันเก่ามาเก็บในอันใหม่
        DataTable dtOrder = (DataTable)Session["dtOrderList"];
        // get row collection
        DataRowCollection drc = dtOrder.Rows;
        // get row to delete
        DataRow delRow = drc.Find(barcode);

        if (delRow != null) drc.Remove(delRow);  
        
        //Response.Write("<script type='text/javascript'>alert('Remove Row completed !!');</script>");

        // refresh data in session
        Session["dtOrderList"] = dtOrder;
        
        // rebind data to gridview again
        dgvOrder.DataSource = Session["dtOrderList"];
        dgvOrder.DataBind(); 
    }
    protected void dgvOrder_RowDeleted(object sender, GridViewDeletedEventArgs e)
    {
        if (e.Exception == null)
        {
            if (e.AffectedRows == 1)
                Response.Write("<script type='text/javascript'>alert('Remove Row completed !!');</script>");
            else
                Response.Write("<script type='text/javascript'>alert('Error occurred during the remove operation !!');</script>");
        }
        else
            e.ExceptionHandled = true;
    }