protected void submitButton_Click(object sender, EventArgs e) { //get the productModle.cs function ProductModel pm = new ProductModel(); //call the createProduct() method Product product = createProduct(); //add new product if (String.IsNullOrWhiteSpace(Request.QueryString["id"])) { //display the resultmessage and call the InSetProduct method from pm which is the productModle.cs productMessageLabel.Text = pm.InSetProduct(product); } //modify existing model update else { //get the existing product id int id = Convert.ToInt32(Request.QueryString["id"]); //use update method productMessageLabel.Text = pm.UpdateProduct(id, product); } }