private void btnEdit_Click(object sender, EventArgs e)
        {
            if (supplierDetailsBindingSource.Current == null)
            {
                return;
            }

            using (AddSupplier am = new AddSupplier(supplierDetailsBindingSource.Current as Supplier_Details))
            {
                if (am.ShowDialog() == DialogResult.OK)
                {
                    supplierDetailsBindingSource.DataSource = cmd.Supplier_Details.ToList();
                }
            }
        }
        private void btnAdd_Click(object sender, EventArgs e)
        {
            AddSupplier a = new AddSupplier(null);

            a.Visible = true;
        }