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;

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>;
  }
}

只需使用mui（material ui）中的ClickAwayListener：

<ClickAwayListener onClickAway={handleClickAway}>
    {children}
<ClickAwayListener >

有关更多信息，请查看：https://mui.com/base/react-click-away-listener/

以上答案中没有一个对我有效，所以我最终做了如下：

从“React”导入React，｛Component｝；

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

    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 (!event.path || !event.path.filter(item => item.className=='classOfAComponent').length) {
      alert('You clicked outside of me!');
    }
  }

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

OutsideAlerter.propTypes = {
  children: PropTypes.element.isRequired,
};

这是最适合我制作下拉菜单的方法：

handleClick = () => {
    document.getElementById("myDrop").classList.toggle("showing");
}

render() {

    return (
        <div className="courses">
            <div class="dropdownBody">
                <button onClick={this.handleClick} onBlur={this.handleClick} class="dropbtn">Dropdown</button>
                <div id="myDrop" class="dropdown-content">
                    <a href="#home">Home</a>
                    <a href="#about">About</a>
                    <a href="#contact">Contact</a>
                </div>
            </div>
        </div>
    )
}

这是我解决问题的方法

我从我的自定义钩子返回一个布尔值，当这个值发生变化时（如果单击在我作为参数传递的ref之外，则为true），这样我就可以用useEffect钩子捕捉到这个变化，我希望你能清楚。

下面是一个活生生的例子：codesandbox上的实时示例

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

const useOutsideClick = (ref) => {
  const [outsieClick, setOutsideClick] = useState(null);

  useEffect(() => {
    const handleClickOutside = (e) => {
      if (!ref.current.contains(e.target)) {
        setOutsideClick(true);
      } else {
        setOutsideClick(false);
      }

      setOutsideClick(null);
    };

    document.addEventListener("mousedown", handleClickOutside);

    return () => {
      document.removeEventListener("mousedown", handleClickOutside);
    };
  }, [ref]);

  return outsieClick;
};

export const App = () => {
  const buttonRef = useRef(null);
  const buttonClickedOutside = useOutsideClick(buttonRef);

  useEffect(() => {
    // if the the click was outside of the button
    // do whatever you want
    if (buttonClickedOutside) {
      alert("hey you clicked outside of the button");
    }
  }, [buttonClickedOutside]);

  return (
    <div className="App">
      <button ref={buttonRef}>click outside me</button>
    </div>
  );
}