Taking a lead (again) from Java generic types for beginners, I decided to experiment with generic types in VB.Net. The ICT Cool blog covers the idea behind generics and the MSDN documentation on generic types in VB.Net gives more details on the topic, so I won’t repeat what has been explained elsewhere.
My code shows how generics can make code more robust by enforcing compile time type checking. The type safety of the various objects can be checked in Visual Studio by hovering the mouse over any of the variables in the code. This brings up a pop up that says the type of the object. Many of the lines of the main sub have been commented out because the project would not build otherwise. Try uncommenting them to see the errors that the IDE finds.
The code also shows that generic types allow coders to build and use type safe, polymorphic collections. Put simply, we can create a list (for example) that will only allow us to add an object of any type, so long as it implements an interface given at the time of construction.