Can't read a const in a class instance?

Question

I was mildly surprised when the compiler complained about this:

public class UsefulClass
{
    public const String RatingName = @\"Ratings\\rating\";
}

publ         


        

Answer 1

A "variable" marked const is a compile time construct, not an instance member. You can access it like you would a static variable:

public void SomeFunc()
{
    UsefulClass useful = new UsefulClass();
    String rating = UsefulClass.RatingName; // Access as if static
}

That being said, I would personally wrap this into a property if it's meant to be used as you described, like so:

public class UsefulClass
{
    private const string ratingName = @"Ratings\rating";

    public string RatingName { get { return ratingName; } }
}

This would make your syntax work, but also be a better design, IMO, since it doesn't expose your constants publically.