Understanding Constructor and Destructor Chaining

In the previous example, you saw how a constructor called a method for a class. But how? That object wasn’t created yet… right?

Well sort of.

When you build from a base/parent class, it’s no arg constructor is called first, creating a base class. That object is then able to call it’s functions.

Let’s try putting some cout statements into the constructors to see the workflow of how objects are created.

Note: Destructors work very similarly. Except in reverse, calling the child class’s destructor, then the parent class’s.

Understanding Constructor and Destructor Chaining was originally found on Access 2 Learn

Walter Wimberly

Assistant Professor

Walter Wimberly is an Assistant Professor at a regional college in Tennessee, teaching Computer Science in the Software Engineering track. He works as a student advisor, oversees curriculum changes, develops new courses, and manages the advisory panel.
Walter taught full time for about 7 years, before going back into “industry” as a full stack Software Developer for a dozen years. There he focused on web based projects coding in JavaScript/jQuery and utilizing the Bootstrap CSS Framework on the front-end, and coding in PHP, ASP/ASP.Net, SQL on the back-end.

Since he loves teaching, he taught as an adjunct web and digital media classes for eight (8) years, while working in industry, and has since returned to teaching full time.

He has been married for over 25 years, and is father to several special needs boys. As such, he is working on some projects to help others who have special needs to be self-sufficient, and support the care givers of those with special needs. Check out his Autism blog for more info.

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