private void readProducts()
 {
     ProductList = new List<Product>();
     String line;
     var file = new System.IO.StreamReader("Product", Encoding.UTF8);
     while ((line = file.ReadLine()) != null)
     {
         Product rNew = new Product();
         String[] parsRec = line.Split('|');
         rNew.IdProduct = parsRec[0];
         rNew.NameProduct = parsRec[1];
         ProductList.Add(rNew);
     }
     file.Close();
 }
        private void checkForNewProduct()
        {
            bool isNew = true;
            foreach (var product in mainForm.ProductList)
            {
                if (product.NameProduct.ToString().Equals(textBox4.Text))
                {
                    isNew = false;
                    newReceptProducts.Add(product);
                }
            }
            if(isNew)
            {
                Product newProduct = new Product();
                newProduct.IdProduct = Guid.NewGuid().ToString();
                newProduct.NameProduct = textBox4.Text;
                mainForm.ProductList.Add(newProduct);
                newReceptProducts.Add(newProduct);
                RecomplitSource();

                rewriteProductsFile();
            }
        }