React Design Patterns and Best Practices - Second Edition

Initializing the state using properties

In this section, we will see how initializing the state using properties received from the parent is usually an anti-pattern. I have used the word usually because, as we will see, once we have it clear in our mind what the problems with this approach are, we might still decide to use it.

One of the best ways to learn something is by looking at the code, so we will start by creating a simple component with a + button to increment a counter.

The component is implemented using a class, as shown in the following snippet of code:

  class Counter extends Component

It has a constructor, where we initialize the state using the count property, and we bind the event handler:

  constructor(props) {     super(props); ...