React教程之封装一个Portal可复用组件的方法(2)

import React from 'react'
import ReactDOM from 'react-dom'
import PropTypes from 'prop-types'
function createPortal() {
 class Portal extends React.Component{
  constructor(props) {
   super(props)
   this.el = document.createElement('div')
   if (!!props) {
    this.el.id = props.id || false
    if (props.className) this.el.className = props.className
    if (props.style) {
     Object.keys(props.style).map((v) => {
      this.el.style[v] = props.style[v]
     })
    }
    document.body.appendChild(this.el)
   }
  }
  componentDidMount() {
   document.body.appendChild(this.el);
  }
  componentWillUnmount() {
   document.body.removeChild(this.el)
  }
  render() {
   return ReactDOM.createPortal(
    this.props.children,
    this.el
   )
  }
 }
 Portal.propTypes = {
  style: PropTypes.object
 }
 return Portal
}
export default createPortal()