参见英文答案 >
Can getDerivedStateFromProps be used as an alternative to componentWillReceiveProps1个
我将React与NextJS一起使用.
我将React与NextJS一起使用.
我有一个组件,基本上是一个表格,给出了一些摘要.
根据一些UI选择,该组件应显示适当的摘要.
以下代码完美无缺.
class Summary extends Component{ state = { total: 0,pass: 0,fail: 0,passp: 0,failp: 0 } componentWillReceiveProps(props){ let total = props.results.length; let pass = props.results.filter(r => r.status == 'pass').length; let fail = total - pass; let passp = (pass/(total || 1) *100).toFixed(2); let failp = (fail/(total || 1) *100).toFixed(2); this.setState({total,pass,fail,passp,failp}); } render() { return( <Table color="teal" > <Table.Header> <Table.Row textAlign="center"> <Table.HeaderCell>TOTAL</Table.HeaderCell> <Table.HeaderCell>PASS</Table.HeaderCell> <Table.HeaderCell>FAIL</Table.HeaderCell> <Table.HeaderCell>PASS %</Table.HeaderCell> <Table.HeaderCell>FAIL %</Table.HeaderCell> </Table.Row> </Table.Header> <Table.Body> <Table.Row textAlign="center"> <Table.Cell>{this.state.total}</Table.Cell> <Table.Cell >{this.state.pass}</Table.Cell> <Table.Cell >{this.state.fail}</Table.Cell> <Table.Cell >{this.state.passp}</Table.Cell> <Table.Cell >{this.state.failp}</Table.Cell> </Table.Row> </Table.Body> </Table> ); } }
看起来不推荐使用componentWillReceiveProps.我尝试了其他选项,如shouldComponentUpdate等.它们都导致无限循环.从props更新状态以重新渲染此组件的最佳方法是什么?
从反应
blog,16.3引入了componentWillRecieveProps的折旧通知.
static getDerivedStateFromProps(nextProps,prevState)
因此
componentWillReceiveProps(props){ let total = props.results.length; let pass = props.results.filter(r => r.status == 'pass').length; let fail = total - pass; let passp = (pass/(total || 1) *100).toFixed(2); let failp = (fail/(total || 1) *100).toFixed(2); this.setState({total,failp}); }
变
static getDerivedStateFromProps(nextProps,prevState) { if (nextProps.total !== prevState.total) { return ({ total: nextProps.total }) // <- this is setState equivalent } etc... }