[React Fundamentals] Component Lifecycle - Updating

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The React component lifecycle will allow you to update your components at runtime. This lesson will explore how to do that.

 

import React from ‘react‘;import ReactDOM from ‘react-dom‘;export default class App extends React.Component {    constructor(){        super();        this.state = {            increasing: false        }    }    update(){        ReactDOM.render(<App val={this.props.val+1} /> , document.getElementById(‘app‘));    }    componentWillReceiveProps(nextProps){        //Invoked when a component is receiving new props. This method is not called for the initial render.        this.setState({            increasing: nextProps.val > this.props.val        })    }    shouldComponentUpdate(nextProps, nextState){        // Control whether the component should re-render        return nextProps.val % 5 === 0; // update dom every 5 clicks    }    render() {        console.log(this.state.increasing);        return (            <div>                <button onClick={this.update.bind(this)}>{this.props.val}</button>            </div>        )    }    componentDidUpdate(prevProps, prevState){        //After DOM update        console.log("prevProps", prevProps);    }}App.defaultProps = {    val: 0}

 

 

[React Fundamentals] Component Lifecycle - Updating