public void addProduct(ProductInformationData pid)
 {
     if(rows==null)
         rows = new System.Collections.Generic.List<ProductInformationData>();
     rows.Add(pid);
     if (!Categories.Contains(pid.ProductCategory.Trim()))
     {
         Categories.Add(pid.ProductCategory);
        // MessageBox.Show("Category Added");
     }
        // MessageBox.Show("Item Added\nid:" + pid.ProductID);
 }
 public ProductInformationData getProductByID(string productID)
 {
     ProductInformationData pid = new ProductInformationData();
     foreach (ProductInformationData item in rows)
     {
         if (item.ProductID.Trim().ToLower().Contains(productID.Trim().ToLower()))
         {
             pid = item;
             break;
         }
     }
     return pid;
 }