Modern C# and .NET Tutorial: Cross-Platform Basics/

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Working with Immutable Collections

Learn about creating immutable collections and the benefits of using concrete types.

We'll cover the following...

Creating an immutable list in C#
- Try it yourself
Good practice with collections
- Performance consideration

Sometimes, we need to make a collection immutable, meaning that its members cannot change, i.e. we cannot add or remove them. If we import the System.Collections.Immutable namespace, then any collection that implements IEnumerable is given six extension methods to convert it into an immutable list, dictionary, hashset, and so on.

Creating an immutable list in C#

Let’s see a simple example of converting the cities list into an immutable list:

Step 1: In the WorkingWithCollections project, in Program.cs, import the ...

Introduction

Hello, C#! Welcome, .NET!

Speaking C#

Controlling Flow, Converting Types, and Handling Exception

Writing, Debugging, and Testing Functions

Building Your Own Types with Object-Oriented Programming

Implementing Interfaces and Inheriting Classes

Packaging and Distributing .NET Types

Working with Common .NET Types

Working with Files, Streams, and Serialization

Working with Data Using Entity Framework Core

Querying and Manipulating Data Using LINQ

Introducing Web Development Using ASP.NET Core

Building Websites Using ASP.NET Core Razor Pages

Building Websites Using the Model-View-Controller Pattern

Building and Consuming Web Services

Building User Interfaces Using Blazor

Conclusion

Working with Immutable Collections

Creating an immutable list in C#