private bool PriceIsValid() { try { double.Parse(ProductPriceTextBox.Text); return(true); } catch (Exception) { MessageBox.Show("Price must be a valid decimal number."); ProductPriceTextBox.Focus(); return(false); } }
// ====================== END OF SEARCH FUNCTIONALITY METHODS ========================= /* * ====================== START OF INVENTORY MANAGEMENT METHODS ========================= * 1.AddProductButton_Click * 2.CategoryButton_Click * 3.ModifyButton_Click */ /* * Event Handler for Adding New Product to Inventory */ private void AddProductButton_Click(object sender, EventArgs e) { Product Prod = new Product(); bool DuplicateProduct = false; StreamWriter FileWriter; FileWriter = File.AppendText(PRODUCTDATABASEFILENAME); if (ProductNameTextBox.Text == "") { MessageBox.Show("Please enter New Product Name"); ProductNameTextBox.Focus(); ProductNameTextBox.SelectAll(); } else { if (ProductCategoryListBox.SelectedIndex == -1) { MessageBox.Show("Please select Product Category from the list"); ProductCategoryListBox.Focus(); } else { if (ProductPriceTextBox.Text == "") { MessageBox.Show("Please enter Product Price"); ProductPriceTextBox.Focus(); ProductPriceTextBox.SelectAll(); } else { try { decimal.TryParse(ProductPriceTextBox.Text, out decimal ProductPrice); if (ProductPrice <= 0) { MessageBox.Show("Product Price should be greater than Zero"); ProductPriceTextBox.Focus(); ProductPriceTextBox.SelectAll(); } else { if (ProductQuantityTextBox.Text == "") { MessageBox.Show("Please enter Product Quantity"); ProductQuantityTextBox.Focus(); ProductQuantityTextBox.SelectAll(); } else { try { int.TryParse(ProductQuantityTextBox.Text, out int ProductQuantity); if (ProductQuantity <= 0) { MessageBox.Show("Product Quantity should be greater than Zero"); ProductQuantityTextBox.Focus(); ProductQuantityTextBox.SelectAll(); } else { foreach (Product p in ProductList) { if (p.ProductCategory == ProductCategoryListBox.SelectedItem.ToString() && p.ProductName == ProductNameTextBox.Text) { MessageBox.Show("Same Product Already Exist in the same Category"); ProductNameTextBox.Focus(); ProductNameTextBox.SelectAll(); DuplicateProduct = true; break; } } if (DuplicateProduct == false) { Random RandomNumberGenerator = new Random(); int ProductNumber = RandomNumberGenerator.Next(1, 999999); string CheckProductID = ProductCategoryListBox.SelectedItem.ToString().Substring(0, 4) + ProductNumber.ToString("D6"); while (ExistProductID_Check(CheckProductID)) { ProductNumber = RandomNumberGenerator.Next(1, 999999); CheckProductID = ProductCategoryListBox.SelectedItem.ToString().Substring(0, 4) + ProductNumber.ToString("D6"); } Prod.ProductID = ProductCategoryListBox.SelectedItem.ToString().Substring(0, 4) + ProductNumber.ToString("D6"); FileWriter.WriteLine(Prod.ProductID); Prod.ProductCategory = ProductCategoryListBox.SelectedItem.ToString(); FileWriter.WriteLine(Prod.ProductCategory); Prod.ProductName = ProductNameTextBox.Text; FileWriter.WriteLine(Prod.ProductName); Prod.ProductPrice = decimal.Parse(ProductPriceTextBox.Text); FileWriter.WriteLine(Prod.ProductPrice); Prod.ProductQuantity = int.Parse(ProductQuantityTextBox.Text); FileWriter.WriteLine(Prod.ProductQuantity); ProductList.Add(Prod); FileWriter.Close(); MessageBox.Show("Product '" + Prod.ProductName + "' Added Successfully to the Category '" + Prod.ProductCategory + "'"); ProductCategoryListBox.SelectedIndex = -1; ProductNameTextBox.Text = ProductPriceTextBox.Text = ProductQuantityTextBox.Text = CheckProductID = ""; } } } catch { } } } } catch { } } } } }