Free mag vol1 | Page 903

CHAPTER 21  ADO.NET PART I: THE CONNECTED LAYER userDone = true; break; default: Console.WriteLine("Bad data! break; } } while (!userDone); Try again"); } catch (Exception ex) { Console.WriteLine(ex.Message); } finally { invDAL.CloseConnection(); } } Implementing the ShowInstructions() Method The ShowInstructions() method does what you would expect, as seen here: private static void ShowInstructions() { Console.WriteLine("I: Inserts a new car."); Console.WriteLine("U: Updates an existing car."); Console.WriteLine("D: Deletes an existing car."); Console.WriteLine("L: Lists current inventory."); Console.WriteLine("S: Shows these instructions."); Console.WriteLine("P: Looks up pet name."); Console.WriteLine("Q: Quits program."); } Implementing the ListInventory() Method You could implement the ListInventory() method in either of two ways, based on how you constructed your data access library. Recall that the GetAllInventoryAsDataTable() method of InventoryDAL returns a DataTable object. You could implement this approach like this: private static void ListInventory(InventoryDAL invDAL) { // Get the list of inventory. DataTable dt = invDAL.GetAllInventoryAsDataTable(); } // Pass DataTable to helper function to display. DisplayTable(dt); The DisplayTable() helper method displays the table data using the Rows and Columns properties of the incoming DataTable (again, you will learn the full details of the DataTable object the next chapter, so don’t fret over the details): 849