React HooksLesson 47Free preview

React useState

This lesson is part of React · All levels

Summary

UseState allows functional components to store data that persists between renders. You declare the pair as the state value and the setter function, then call the setter to trigger the rendering. For objects or arrays, always make a new copy when updating so that changes are detected by React.

Key points

Written with const
The setter call triggers the component rendering
Immutably update objects and arrays
The initial value is only used on the first render.

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