React, Hooks, State, Effect

Stores the previous state or props.

  • Create a custom hook that takes a value.
  • Use the useRef() hook to create a ref for the value.
  • Use the useEffect() hook to remember the latest value.
const usePrevious = value => {
  const ref = React.useRef();
  React.useEffect(() => {
    ref.current = value;
  return ref.current;
const Counter = () => {
  const [value, setValue] = React.useState(0);
  const lastValue = usePrevious(value);

  return (
        Current: {value} - Previous: {lastValue}
      <button onClick={() => setValue(value + 1)}>Increment</button>

ReactDOM.render(<Counter />, document.getElementById('root'));

Recommended snippets

  • useMediaQuery

    React, Hooks

    Checks if the current environment matches a given media query and returns the appropriate value.

  • usePersistedState

    React, Hooks

    Returns a stateful value, persisted in localStorage, and a function to update it.

  • useKeyPress

    React, Hooks

    Listens for changes in the pressed state of a given key.