constructor - C# How to execute code after object construction (postconstruction)

Question

As you can see in the code below, the DoStuff() method is getting called before the Init() one during the construction of a Child object.

I'm in a situation where I have numerous child classes. Therefore, repeating a call to the DoStuff() method directly after Init() in the constructor of each child wouldn't be an elegant solution.

Is there any way I could create some kind of post constructor in the parent class that would be executed after the child's constructor? This way, I could call to the DoStuff() method there.

If you have any other design idea which could solve my problem, I'd like to hear it too!

abstract class Parent
{
    public Parent()
    {
        DoStuff();
    }

    protected abstract void DoStuff();
}

class Child : Parent
{
    public Child()
    // DoStuff is called here before Init
    // because of the preconstruction
    {
        Init();
    }

    private void Init()
    {
        // needs to be called before doing stuff
    }

    protected override void DoStuff() 
    {
        // stuff
    }
}

Answer 1

If you have a complex logic for constructing your objects then consider FactoryMethod pattern.

In your case I would implement it as a simple

public static Parent Construct(someParam)

method that takes some parameter and based on it decides which child class to instantiate. You can remove your DoStuff() method call from the constructor and call it inside Construct() on the new instance.

Also, you should avoid virtual/abstract method calls in the constructors. See this question for more details: Virtual member call in a constructor