我在discuss.reactjs.org上找到了一个解决方案，这要感谢Ben Alpert。单击我的树中的一个组件会导致一个重新阅读程序，在更新时删除了单击的元素。由于React的重读发生在调用文档正文处理程序之前，因此元素未被检测为“在”树中。

解决方案是在应用程序根元素上添加处理程序。

主要：

window.__myapp_container = document.getElementById('app')
React.render(<App/>, window.__myapp_container)

组件：

import { Component, PropTypes } from 'react';
import ReactDOM from 'react-dom';

export default class ClickListener extends Component {

  static propTypes = {
    children: PropTypes.node.isRequired,
    onClickOutside: PropTypes.func.isRequired
  }

  componentDidMount () {
    window.__myapp_container.addEventListener('click', this.handleDocumentClick)
  }

  componentWillUnmount () {
    window.__myapp_container.removeEventListener('click', this.handleDocumentClick)
  }

  /* using fat arrow to bind to instance */
  handleDocumentClick = (evt) => {
    const area = ReactDOM.findDOMNode(this.refs.area);

    if (!area.contains(evt.target)) {
      this.props.onClickOutside(evt)
    }
  }

  render () {
    return (
      <div ref='area'>
       {this.props.children}
      </div>
    )
  }
}

这已经有很多答案了，但它们没有解决e.stopPropagation（）和阻止单击要关闭的元素之外的react链接的问题。

由于React有自己的人工事件处理程序，您无法将文档用作事件侦听器的基础。在这之前，您需要e.stopPropagation（），因为React使用文档本身。如果改用document.querySelector（'body'）。您可以防止点击React链接。下面是我如何实现单击外部并关闭的示例。这使用ES6和React 16.3。

import React, { Component } from 'react';

class App extends Component {
  constructor(props) {
    super(props);

    this.state = {
      isOpen: false,
    };

    this.insideContainer = React.createRef();
  }

  componentWillMount() {
    document.querySelector('body').addEventListener("click", this.handleClick, false);
  }

  componentWillUnmount() {
    document.querySelector('body').removeEventListener("click", this.handleClick, false);
  }

  handleClick(e) {
    /* Check that we've clicked outside of the container and that it is open */
    if (!this.insideContainer.current.contains(e.target) && this.state.isOpen === true) {
      e.preventDefault();
      e.stopPropagation();
      this.setState({
        isOpen: false,
      })
    }
  };

  togggleOpenHandler(e) {
    e.preventDefault();

    this.setState({
      isOpen: !this.state.isOpen,
    })
  }

  render(){
    return(
      <div>
        <span ref={this.insideContainer}>
          <a href="#open-container" onClick={(e) => this.togggleOpenHandler(e)}>Open me</a>
        </span>
        <a href="/" onClick({/* clickHandler */})>
          Will not trigger a click when inside is open.
        </a>
      </div>
    );
  }
}

export default App;

我之所以这样做，部分原因是遵循了这一点，并遵循了React官方文件关于处理需要React ^16.3的参考文献。这是我在尝试了其他一些建议之后唯一有效的方法。。。

class App extends Component {
  constructor(props) {
    super(props);
    this.inputRef = React.createRef();
  }
  componentWillMount() {
    document.addEventListener("mousedown", this.handleClick, false);
  }
  componentWillUnmount() {
    document.removeEventListener("mousedown", this.handleClick, false);
  }
  handleClick = e => {
    /*Validating click is made inside a component*/
    if ( this.inputRef.current === e.target ) {
      return;
    }
    this.handleclickOutside();
  };
  handleClickOutside(){
    /*code to handle what to do when clicked outside*/
  }
  render(){
    return(
      <div>
        <span ref={this.inputRef} />
      </div>
    )
  }
}

除了.concurs之外，还可以使用最接近的方法。当您想检查单击是否在id=“apple”的元素之外时，我可以使用：

const isOutside = !e.target.closest("#apple");

这将检查单击的树上方的树中是否有任何元素的id为“apple”。我们必须否定结果！

以下解决方案使用ES6并遵循绑定以及通过方法设置ref的最佳实践。

要将其付诸行动：

挂钩实施反应16.3后的类实现反应16.3之前的类实现

挂钩实施：

import React, { useRef, useEffect } from "react";

/**
 * Hook that alerts clicks outside of the passed ref
 */
function useOutsideAlerter(ref) {
  useEffect(() => {
    /**
     * Alert if clicked on outside of element
     */
    function handleClickOutside(event) {
      if (ref.current && !ref.current.contains(event.target)) {
        alert("You clicked outside of me!");
      }
    }
    // Bind the event listener
    document.addEventListener("mousedown", handleClickOutside);
    return () => {
      // Unbind the event listener on clean up
      document.removeEventListener("mousedown", handleClickOutside);
    };
  }, [ref]);
}

/**
 * Component that alerts if you click outside of it
 */
export default function OutsideAlerter(props) {
  const wrapperRef = useRef(null);
  useOutsideAlerter(wrapperRef);

  return <div ref={wrapperRef}>{props.children}</div>;
}

类实现：

16.3之后

import React, { Component } from "react";

/**
 * Component that alerts if you click outside of it
 */
export default class OutsideAlerter extends Component {
  constructor(props) {
    super(props);

    this.wrapperRef = React.createRef();
    this.handleClickOutside = this.handleClickOutside.bind(this);
  }

  componentDidMount() {
    document.addEventListener("mousedown", this.handleClickOutside);
  }

  componentWillUnmount() {
    document.removeEventListener("mousedown", this.handleClickOutside);
  }

  /**
   * Alert if clicked on outside of element
   */
  handleClickOutside(event) {
    if (this.wrapperRef && !this.wrapperRef.current.contains(event.target)) {
      alert("You clicked outside of me!");
    }
  }

  render() {
    return <div ref={this.wrapperRef}>{this.props.children}</div>;
  }
}

16.3之前

import React, { Component } from "react";

/**
 * Component that alerts if you click outside of it
 */
export default class OutsideAlerter extends Component {
  constructor(props) {
    super(props);

    this.setWrapperRef = this.setWrapperRef.bind(this);
    this.handleClickOutside = this.handleClickOutside.bind(this);
  }

  componentDidMount() {
    document.addEventListener("mousedown", this.handleClickOutside);
  }

  componentWillUnmount() {
    document.removeEventListener("mousedown", this.handleClickOutside);
  }

  /**
   * Set the wrapper ref
   */
  setWrapperRef(node) {
    this.wrapperRef = node;
  }

  /**
   * Alert if clicked on outside of element
   */
  handleClickOutside(event) {
    if (this.wrapperRef && !this.wrapperRef.contains(event.target)) {
      alert("You clicked outside of me!");
    }
  }

  render() {
    return <div ref={this.setWrapperRef}>{this.props.children}</div>;
  }
}

我对所有其他答案最担心的是必须从根/父级向下过滤单击事件。我发现最简单的方法是简单地设置一个具有位置的同级元素：fixed，下拉列表后面的z索引1，并处理同一组件内固定元素上的单击事件。将所有内容集中到给定组件。

示例代码

#HTML
<div className="parent">
  <div className={`dropdown ${this.state.open ? open : ''}`}>
    ...content
  </div>
  <div className="outer-handler" onClick={() => this.setState({open: false})}>
  </div>
</div>

#SASS
.dropdown {
  display: none;
  position: absolute;
  top: 0px;
  left: 0px;
  z-index: 100;
  &.open {
    display: block;
  }
}
.outer-handler {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    opacity: 0;
    z-index: 99;
    display: none;
    &.open {
      display: block;
    }
}