public static FrmCreateOrder getInstance()
 {
     if (instance == null || instance.IsDisposed)
     {
         instance = new FrmCreateOrder();
     }
     return(instance);
 }
        private void btnAdd_Click(object sender, EventArgs e)
        {
            FrmCreateOrder frmCreateOrder = (FrmCreateOrder)this.Owner;

            frmCreateOrder.addDgvRow(cmbType.Text, tbxUnitPrice.Text, mtbQty.Text, tbxTotal.Text);
            frmCreateOrder.addToTotal(tbxTotal.Text);

            mtbQty.Clear();
            tbxTotal.Clear();

            btnAdd.Enabled = false;
        }
 private void btnCreateOrder_Click(object sender, EventArgs e)
 {
     CreateNewOrder.FrmCreateOrder createrOrderFrm = CreateNewOrder.FrmCreateOrder.getInstance();
     createrOrderFrm.Show();
     createrOrderFrm.BringToFront();
 }