"const correctness" in C#

The point of const-correctness is to be able to provide a view of an instance that can't be altered or deleted by the user. The compiler supports this by pointing out when you break constness from within a const function, or try to use a non-const function of a const object. So without copying the const approach, is there a methodology I can use in C# that has the same ends?

I'm aware of immutability, but that doesn't really carry over to container objects to name but one example.

I've come across this issue a lot of times too and ended up using interfaces.

I think it's important to drop the idea that C# is any form, or even an evolution of C++. They're two different languages that share almost the same syntax.

I usually express 'const correctness' in C# by defining a read-only view of a class:

public interface IReadOnlyCustomer
{
    String Name { get; }
    int Age { get; }
}

public class Customer : IReadOnlyCustomer
{
    private string m_name;
    private int m_age;

    public string Name
    {
        get { return m_name; }
        set { m_name = value; }
    }

    public int Age
    {
        get { return m_age; }
        set { m_age = value; }
    }
}

To get the benefit of const-craziness (or pureness in functional programming terms), you will need to design your classes in a way so they are immutable, just like the String class of c# is.

This approach is way better than just marking an object as readonly, since with immutable classes you can pass data around easily in multi-tasking environments.

I just wanted to note for you that many of the System.Collections.Generics containers have an AsReadOnly method which will give you back an immutable collection.

C# doesn't have such feature. You can pass argument by value or by reference. Reference itself is immutable unless you specify ref modifier. But referenced data isn't immutable. So you need to be careful if you want to avoid side effects.

MSDN:

Passing Parameters