/Javascript/React/Reducer in react example

Reducer in react example

const initialState = {count: 0};

function reducer(state, action) {
  switch (action.type) {
    case 'increment':
      return {count: state.count + 1};
    case 'decrement':
      return {count: state.count - 1};
    default:
      throw new Error();
  }
}

function Counter() {
  const [state, dispatch] = useReducer(reducer, initialState);
  return (
    <>
      Count: {state.count}
      <button onClick={() => dispatch({type: 'decrement'})}>-</button>
      <button onClick={() => dispatch({type: 'increment'})}>+</button>
    </>
  );
}

Source: reactjs.org

Similar codes

105 votes202 views1 answer
React simbu
Javascript React
5 votes163 views1 answer
How to host react app on heroku
Javascript React
0 vote137 views1 answer
'{ state: any; dispatch: React.Dispatch<{ type: string; payload: any; }>; }' is not assignable to type 'Store'
Javascript React
0 vote169 views4 answers
Reactnative sliding image
Javascript React
92 votes168 views6 answers
React router dom
Javascript React
0 vote169 views2 answers
React hotjar
Javascript React
0 vote225 views1 answer
React avoid spreading non-dom props across component
Javascript React
0 vote169 views1 answer
How to use adminlte in reacts
Javascript React
1 vote166 views2 answers
How to not use relative imports in react js
Javascript React
-1 vote164 views1 answer
React localstorage remove item
Javascript React