Lesson 17 - Indexers, Equals, constants, enumerated types and flags
In the previous exercise, Solved tasks for OOP in C# .NET lessons 14-16, we've practiced our knowledge from previous lessons.
In the previous lesson, Solved tasks for OOP in C# .NET lessons 14-16, we went over abstract classes and learned how to overload operators in C# .NET. The last 3 lessons were very practical, as in lots of doing and getting right into sample programs. This time around we're going to get back into theoretical concepts for a little bit.
Indexers
Similarly, as we could overload an operator, in our own class, we can overload the indexer as well. We know indexers very well from collections, we use them as brackets [] and they allow us to work with classes as if they were collections. We can index both by numbers or strings. Let's make a quick little class:
class CustomCollection { private List<int> internalCollection = new List<int>(new int[] {1, 2, 3, 4, 5}); }
The class contains an internal collection of 5 numbers, where we will now implement a custom indexer. In .NET, we implement indexers as properties. They are declared like this:
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