Set properties of a class only through constructor

Question

I am trying to make the properties of class which can only be set through the constructor of the same class.

Answer 1

With C# 9 it introduces 'init' keyword which is a variation of 'set', which is the best way to do this.

The one big limitation today is that the properties have to be mutable for object initializers to work: They function by first calling the object’s constructor (the default, parameterless one in this case) and then assigning to the property setters.

Init-only properties fix that! They introduce an init accessor that is a variant of the set accessor which can only be called during object initialization:

public class Person
{
    public string FirstName { get; init; }
    public string LastName { get; init; }
}

Ref: https://devblogs.microsoft.com/dotnet/welcome-to-c-9-0/