#695 – Static Methods Can Access Static Members

A static method can only access static members in the class that it’s defined in.

(If you pass an instance of an object to a static method, it can invoke instance members on that object).

    public class Dog
    {
        // Instance properties
        public string Name { get; set; }
        public int Age { get; set; }

        // Instance constructor
        public Dog(string name, int age)
        {
            Name = name;
            Age = age;
        }

        // Instance method
        public void Bark()
        {
            Console.WriteLine("{0} says WOOF", Name);
        }

        // Static property
        public static string DogMotto { get; protected set; }

        // Static constructor
        static Dog()
        {
            DogMotto = "Serve humans";
        }

        // Static method
        public static void AboutDogs()
        {
            // Accessing static data
            Console.WriteLine("Dogs believe: {0}", DogMotto);

            // ERROR: Can't access instance property
            Console.WriteLine(Name);

            // ERROR: Can't call instance method
            Bark();
        }
    }

Trying to access instance methods or data from a static member will generate a 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.

3 Responses to #695 – Static Methods Can Access Static Members

  1. Jack Moorhead says:

    If you wanted to access the instance method Bark(), how would you do it in your example?

    • Sean says:

      Jack, you can’t access instance methods–that was the point of the post. A static method is one that executes without knowing anything about any particular instance. So if our AboutDogs() method is static, it’s not specific to any particular Dog instance. So calling Bark() doesn’t make sense, since we don’t know which Dog we’re talking about.

  2. Jack Moorhead says:

    I read through your previous posts and created an object
    Dog spook = new Dog(“Spook”, 11);
    and then access the methods using a reference…
    Console.WriteLine(spook.Name);
    spook.Bark();

    Correct?

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