react 实现聊天界面，发送消息自动到底部

<div style={{ float:"left", clear: "both" }}
                         ref={(el) => { this.messagesEnd = el; }}>
</div>      

  scrollToBottom = () => {
    this.messagesEnd.scrollIntoView({ behavior: "auto" });
  }

  componentDidUpdate(prevProps, prevState, snapshot) {
    const { message } = this.state;
    this.scrollToBottom();

  }

  componentDidMount() {
      this.scrollToBottom();
}