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Kayut
Kayut

Posted on

Class definition in React

#react #help

Does a Class component in React need to have a constructor like the following example:

class App extends React.Component { constructor() { super() this.state = { count: 0 } } render() { ... } }

Or now we can define a Class component without using a constructor, like the following example?:

class App extends React.Component { this.state = { count: 0 } render() { ... } }

Which one is correct?
Do we still need to write the constructor for a Class component?

Top comments (3)

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10secondsofcode profile image
Elango Sundar •

@kayut If you don't have child class means, you can use as second option like without constructor.

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kozakrisz profile image
Krisztian Kecskes •

dev.to/kozakrisz/react---es6-trick...

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dance2die profile image
Sung M. Kim •

👆 answers the question 👍

@kayut
And note that the state is initialized as a property outside of constructor, this. should be dropped.

class App extends React.Component { // not this.state but just state state = { count: 0 }; render() { ... } }