#791 – Properties Are Not Variables

A property cannot be used in the same way as a variable, like a field can.

A field is a variable that is defined within a class and it denotes an actual storage location.  Because it refers to a storage location, you can pass a field by reference, using a ref or out keyword on the argument.

If Name is a public field of a Dog class, you can do this:

        static void Main(string[] args)
        {
            Dog d = new Dog("Bob");

            MakeNoble(ref d.Name);
        }

        private static void MakeNoble(ref string name)
        {
            name = "Sir " + name;
        }

A property, on the other hand, is not a variable and its name does not refer directly to a storage location.  So you can’t pass a property as a ref or out argument to a method.

            Dog d = new Dog("Bob");
            d.Age = 5;
            AgeMe(ref d.Age);  // Compile-time Error
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About Sean
Software developer in the Twin Cities area, passionate about .NET technologies. Equally passionate about my own personal projects related to family history and preservation of family stories and photos.

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