#385 – A Delegate Instance Can Refer to Both Instance and Static Methods

A delegate instance in C# can refer to one or more methods that all have a particular signature.  You can assign a single method to the delegate using the assignment (=) operator.  You can also add or remove methods from the delegate’s invocation list using the addition assignment (+=) and subtraction assignment (-=) operators.

The delegate can refer to both instance and static methods.  Internally, the delegate will store a reference to either a static method or to an instance method as well as the specific object to invoke the instance method on.

        public delegate void StringDelegate(string s);

        static void Main()
        {
            // First method on invocation list--instance method
            Dog kirby = new Dog("Kirby");
            StringDelegate del = kirby.Bark;

            // 2nd method on invocation list--static method
            del += LogABark;

            // Invoke methods on invocation list--both static and instance methods in this case
            del("Growf!");
        }

        static void LogABark(string bark)
        {
            Console.WriteLine("Logging bark [{0}]", bark);
        }

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About Sean
Software developer in the Twin Cities area, passionate about software development and sailing.

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