Microsoft Certified Solutions Developer (MCSD) Certification Practice Test

What is an indexer in C#?

1. A method for defining a class

2. A property with a key

3. A way to access class instances like arrays

4. A way to create delegates

The correct answer is: A way to access class instances like arrays

An indexer in C# allows an object to be indexed in a similar way to arrays. It provides a way to access the elements of a class or struct using an index, which makes it feel like you are working with an array. This is particularly useful for classes that represent collections of objects, as it improves the readability and usability of the code. By defining an indexer, you can specify how to retrieve values based on an index. For instance, if you have a class that represents a list of strings, you can define an indexer that allows access to those strings using an integer index, just as you would with a standard array. This capability enhances encapsulation and provides a more intuitive way to interact with data encapsulated in classes. Contextually, while a property with a key could describe aspects of how data is stored or retrieved, it does not encapsulate the full semantic functionality of what an indexer provides. Similarly, while a method for defining a class could refer to using constructors or other initialization methods, it does not capture the indexing behavior of classes. Lastly, creating delegates pertains to other programming constructs and does not relate to how instances of classes are accessed like arrays. Overall, the primary purpose of an indexer is to facilitate