System.Collections namespace, while the more type-safe generic collections are found in the System.Collections.Generic namespace.In many scenarios, you might want to prevent changes to the data stored in a collection once it’s been initialized. This is where immutable objects and read-only collections come into play. An immutable object is one that cannot be modified after its creation, ensuring the integrity of the data. While not all collections are inherently immutable, .NET Core offers several read-only collection types that can be used to implement immutability in your applications. These include IReadOnlyList, IReadOnlyDictionary, and IReadOnlyCollection, all of which reside in the System.Collections.Generic namespace.
These read-only collection types are ideal for scenarios where you need to ensure that the data is not altered once it has been assigned. For example, IReadOnlyList<T> provides a way to store data in a list that can be read but not modified, while IReadOnlyDictionary<TKey, TValue> offers a similar contract for key-value pairs. IReadOnlyCollection<T> is a more general interface for collections that allows read-only access to the elements. These types help safeguard your data and make your code more predictable, especially in multithreaded or highly concurrent environments.
In this article, we’ll explore how to work with these read-only immutable collection types in C# and how to implement them in your projects. To follow along with the examples provided, you should have Visual Studio 2019 installed on your machine. If you haven’t already done so, you can download Visual Studio 2019 from the official website. By understanding and using these read-only collections, you can take advantage of the benefits of immutability and create safer, more reliable applications.