private void addNewProductToolStripMenuItem_Click(object sender, EventArgs e) { NewProductForm newProductform = new NewProductForm(ref m_register); DialogResult tempDR = newProductform.ShowDialog(); Product toAdd; if (tempDR != DialogResult.OK) { return; } toAdd = newProductform.ProductToAdd; m_register.Products.Add(toAdd); foreach (Control c in m_inventoryTab.Controls) { if (c is InventoryControl) { InventoryControl inv = c as InventoryControl; inv.UpdateInventory(); } } m_register.Save(); }