Visual Basic® 2010 Unleashed

Grouping Operators

The grouping concept is something that you of course already know if you ever worked with data. Given a products collection, it would be useful dividing products into categories to provide a better organization of information. For example, consider the following Category class:

Now consider the following review of the Product class, with a new CategoryID property:

At this point we can write code that creates instances of both classes and populates appropriate collections, as in the following snippet:

To make things easier to ...