private void factor_btn_Click(object sender, EventArgs e)
{
Item_SheetFactor Sheet = new Item_SheetFactor(qty_num.Value,partnum_txt.Text);
Sheet.ShowDialog();
qty_num.Value = Sheet.FactoredWeight;
EngWBDS.Tables["ECOMtl"].Rows[BillDataGrid.CurrentCellAddress.Y]["QtyPer"] = qty_num.Value;
Sheet.Dispose();
}