Liskov Substitution Principle

Liskov Substitution principle states “Derived class must be substitute of parent class.” In JS method of child component must be exact replica of method of parent component.

The method in child component should be exact number of arguments, exact types of arguments and exact return type as parent (types referring to typescript).

Simply put, you should be able to replace a parent component with a child component that behaves in the same way. This makes the code more flexible and easier to scale.

Here as we can see, we are using BtnTwo in BtnOne component and in both component print method is same only. That method can be replaced in both component with each other. So, we can write the same code as below :-

In less number of lines where print method is interchangeable between BtnOne and BtnTwo. Which fulfills the Liskov Substitution principle.