Custom Immutable Class

Creating an immutable class in C# ensures that once an instance is created, its state cannot be modified. This is useful for Creating reliable and thread-safe objects. Here’s how you can achieve this: 

1- Use readonly fields and initialize them through the constructor. 

2- Avoid setters for properties. 

3- Mark the class as sealed to prevent inheritance (optional). Here’s a simple example:

public sealed class ImmutablePerson
{
    public readonly string FirstName { get; }
    public readonly string LastName { get; }

    public ImmutablePerson(string firstName, string lastName)
    {
        FirstName = firstName;
        LastName = lastName;
    }
    public string GetFullName()
    {
      return  $"{FirstName} {LastName}"
    }
}

var person = new ImmutablePerson("John", "Doe");
 Console.WriteLine(person.GetFullName());

In this example: 

1- The FirstName and LastName properties are read-only. 

2- The only way to set FirstName and LastName is through the constructor. 

3- The class is sealed to prevent modification through inheritance.