#689 – References and Objects

A variable whose type is a reference type can be declared without making the variable point to an instance of that type (an object).  At this point, the value of the variable will be null.

A reference-typed variable can later be assigned to refer to an instance of the appropriate type, or it can be assigned at the point where it is declared.

            Dog myDog;
            myDog = new Dog("Kirby", 13);

            Dog yourDog = new Dog("Ruby", 2);

A reference-typed variable can be re-assigned to refer to a difference instance of the type.  (If an object is no longer referenced by any variables, it will eventually be garbage collected).

            Dog jack = new Dog("Jack", 15);
            Dog kirby = new Dog("Kirby", 13);

            Dog currentDog = jack;
            currentDog = kirby;

Notice also in this example that more than one reference-typed variable can refer to the same object.

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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.

One Response to #689 – References and Objects

  1. Pingback: #921 – Objects Are Explicitly Created but Automatically Destroyed | 2,000 Things You Should Know About C#

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