React 学习——useReducer

import  {Button} from 'antd'
import { useReducer } from 'react';

function reducer(state,action){
  switch(action.type){
    case 'add':
      return state + 1;
    case 'del':
      return state - 1;
    case 'set':
      return action.payload;
    default:
      return state; 
  }
}
const App = () => {
  const [state,dispatch] = useReducer(reducer,0)
  return (
    <div className="home">
      {state}<br />
      <Button type="primary" onClick={()=>dispatch({type:'add'})}>测试reducer+</Button><br />
      <Button type="primary" onClick={()=>dispatch({type:'del'})}>测试reducer-</Button><br />
      <Button type="primary" onClick={()=>dispatch({type:'set',payload:100})}>测试reducer-传固定100参数</Button>
    </div>
  )
}

export default App