Beginning C# 3.0

12.1. What are Generics?

The best way to appreciate what generics bring to the programming table is with an example. Sorting data is a very common programming problem. I once was interviewed for a consulting job and part of the interview was a programming test in which I was expected to generate a series of random numbers, display them in a listbox, sort them into ascending order, and redisplay them in a second listbox. The interviewers weren't happy when I bypassed writing my own sort routine and simply turned on the Sorted property in the second listbox. Moral: know your toolkit. But suppose you have to sort a series of integer data into ascending order and you can't use the listbox trick. How would you write the solution?

Try It Out: Quicksort While volumes have been written on sorting algorithms, one of the fastest general-purpose sorts is the Quicksort. The algorithm uses a divide-and-conquer approach to partitioning the data and then calls itself recursively to perform the sorting task. A sample run of the program is shown in Figure 12-1. Figure 12-1. Figure 12-1 The listbox object on the left shows the "raw" data produced by the generation of 10 integer values using the pseudo-random number class (Random). After the user clicks the Sort button, that same list of numbers is sorted and then displayed in the second listbox object. (No, I didn't take the shortcut and simply ...