The
componentDidUpdate()
format of the method is as follows:
componentDidUpdate(prevProps, prevState, snapshot)
componentDidUpdate()
method is called immediately after the build update.
This method is not performed for the first time rendering.
You can also do it at
componentDidUpdate()
call directly in the
setState()
. But note that it must be wrapped in a conditional statement
The following examples use the
componentDidUpdate()
method is executed after the build is updated, and the build uses the
componentDidMount()
. The method will be found in the
1
modification operation occurs after a second: 3.19.1. Example ¶
classHeaderextendsReact.Component{constructor(props){super(props);this.state=
{favoritesite:"runoob"};}componentDidMount(){setTimeout(()=>{this.setState
({favoritesite:"google"})},1000)}componentDidUpdate(){document.getElementById("mydiv").
innerHTML="What I like after the update is"+this.state.favoritesite;}render(){return(<div>
<h1>My favorite website is{this.state.favoritesite}</h1> <divid="mydiv"></div>
</div>);}}ReactDOM.render(<Header/>,document.getElementById('root'));