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JavaScript

Posted by Sunny Chu
Sunny Chu
4,677 Points

React - when to use class & when to just use variable?

I notice in "React by Example" tutorial. That the app component is set as a class

class App extends Component { ...... }

But for other component like guestlist, guest, guestname. They are all just using a file and set it as variable like:

const Guest = props =>
Guest.propTypes = { .... }

It seems like it's doing very similar thing, so what is the difference between using class and variable in React? And are their any special consideration factor when choosing which to use?

2 Answers

Thomas Gauperaa
Thomas Gauperaa
3,584 Points

Sunny, components declared like "const Guest = props =>" and so on are "functional components" that only have a render method. If you use "class" you get a component that can have its own state, constructor, functions and render method. Tip: if you use class then remember that props need to be written "this.props.myProp", not just "props.myProp" like in a functional component. Hope this helps.

Sunny Chu
Sunny Chu
4,677 Points
Sunny Chu
Sunny Chu
4,677 Points

Thanks Thomas! it clears up a good deal of question for me.