React父组件调用子组件

import React, {Component} from ‘react‘;
import ChildComponent from ‘./child‘;
export default class ParentComponent extends Component {
    render() {
        return(
            <div>
                <ChildComponent onRefChild={this.onRefChild} />
                <button onClick={this.clickParent.bind(this)} >{‘点击‘}</button>
            </div>
        )
    }

    onRefChild = (ref) => {
        this.child = ref
    }

    clickParent = (e) => {
        this.child.childMethods()
    }

}

import React, {Component} from ‘react‘;
export default class ParentComponent extends Component {
    componentDidMount(){
        this.props.onRefChild(this)
    }

    childMethods = () => alert(‘子组件被执行了‘)

    render() {
        return (<div>我是子组件</div>)
    }

}