// Update supplier private void btnUpdate_Click(object sender, EventArgs e) { // valid supplier id if (!Validator.IsValidSupplierId(supplierId.Text, out string result)) { MessageBox.Show(result, "Supplier Error"); return; } // supplier name required as per Jolanta if (string.IsNullOrEmpty(supplierName.Text)) { MessageBox.Show("Supplier Name is required.", "Supplier Error"); return; } Supplier supplier = new Supplier() { SupplierId = Convert.ToInt32(supplierId.Text), SupName = supplierName.Text }; SuppliersDB.EditSupplier(supplier); this.DialogResult = DialogResult.OK; }