#714 – Accessibility of a Public Method in an Internal Type

When you declare a class with an accessibility of internal, the class is usable only from code within the same assembly.  If this class then contains a member whose accessibility is public, that member is still limited to an accessibility level of internal.  A member of a class cannot be more accessible than the class itself.

This makes sense.  If we have code that doesn’t know about about a DogCollar class, it certainly can’t invoke the ReportSize method of the DogCollar class.

    // Can only use DogCollar within this assembly
    internal class DogCollar
    {
        // Marked as public, but effectively internal
        public double Size { get; set; }

        public DogCollar(double size)
        {
            Size = size;
        }

        // Also effectively internal
        public void ReportSize()
        {
            Console.WriteLine(string.Format("Collar is {0} in long", Size));
        }
    }