react 严格模式this.refs失效

可以用新写法 myRef = React.createRef();

import React from "react";
export default class App extends React.Component {
  ipt = React.createRef();
  render() {
    return (
      <div>
        <input ref={this.ipt}></input>
        <button onClick={() => {
          console.log(this.ipt.current.value);

        }}>点击</button>
      </div>
    )
  }
}

文档:Refs and the DOM – React (reactjs.org)