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Last active February 8, 2023 12:11
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Compare two ways of getting previous state from a React component, when setting its new state.
class Player extends React.Component {
constructor() {
super()
this.state = { score: 0 }
}
increaseScore() {
// 1. Get previous state from this.state
this.setState({ score: this.state.score + 1 })
// 2. Get previous state from the callback function
this.setState((prevState) => {
return { score: prevState.score + 1 }
})
}
}
@frayhan32
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Awesome thank you

@piotros
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piotros commented Aug 17, 2018

Second example can look like this:

this.setState(prevState => ({
    score: prevState.score + 1
})

@nikhilknoldus
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👍

@pawan-prusty
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How to do this with functional component

@shoaib9121
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@pawan-prusty With functional component you could do something like below:

const [score, setScore] = React.useState(0);

and somewhere later in the code

setScore(prevState => {
   return prevState + 1;
})

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