所以我遇到了一个类似的问题，但在我的案例中，这里选择的答案不起作用，因为我有一个下拉菜单按钮，这是文档的一部分。因此，单击该按钮也会触发handleClickOutside函数。为了防止触发，我必须向按钮和这个添加一个新的引用！menuBtnRef.current.contents（e.target）设置为条件。如果有人像我一样面临同样的问题，我就把它留在这里。

下面是组件现在的样子：

const Component = () => {

    const [isDropdownOpen, setIsDropdownOpen] = useState(false);
    const menuRef     = useRef(null);
    const menuBtnRef  = useRef(null);

    const handleDropdown = (e) => {
        setIsDropdownOpen(!isDropdownOpen);
    }

    const handleClickOutside = (e) => {
        if (menuRef.current && !menuRef.current.contains(e.target) && !menuBtnRef.current.contains(e.target)) {
            setIsDropdownOpen(false);
        }
    }

    useEffect(() => {
        document.addEventListener('mousedown', handleClickOutside, true);
        return () => {
            document.removeEventListener('mousedown', handleClickOutside, true);
        };
    }, []);

    return (

           <button ref={menuBtnRef} onClick={handleDropdown}></button>

           <div ref={menuRef} className={`${isDropdownOpen ? styles.dropdownMenuOpen : ''}`}>
                // ...dropdown items
           </div>
    )
}

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

const YourComponent: React.FC<ComponentProps> = (props) => {
  const ref = useRef<HTMLDivElement | null>(null);
  const [myState, setMyState] = useState(false);
  useEffect(() => {
    const listener = (event: MouseEvent) => {
      // we have to add some logic to decide whether or not a click event is inside of this editor
      // if user clicks on inside the div we dont want to setState
      // we add ref to div to figure out whether or not a user is clicking inside this div to determine whether or not event.target is inside the div
      if (
        ref.current &&
        event.target &&
        // contains is expect other: Node | null
        ref.current.contains(event.target as Node)
      ) {
        return;
      }
      // if we are outside
      setMyState(false);
    };
    // anytime user clics anywhere on the dom, that click event will bubble up into our body element
    // without { capture: true } it might not work
    document.addEventListener("click", listener, { capture: true });
    return () => {
      document.removeEventListener("click", listener, { capture: true });
    };
  }, []);

  return (
    <div  ref={ref}>
      ....
    </div>
  );
};

import { RefObject, useEffect } from 'react';

const useClickOutside = <T extends HTMLElement>(ref: RefObject<T>, fn: () => void) => {
    useEffect(() => {
        const element = ref?.current;
        function handleClickOutside(event: Event) {
            if (element && !element.contains(event.target as Node | null)) {
                fn();
            }
        }
        document.addEventListener('mousedown', handleClickOutside);
        return () => {
            document.removeEventListener('mousedown', handleClickOutside);
        };
    }, [ref]);
};

export default useClickOutside;

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;

这是我的方法（演示-https://jsfiddle.net/agymay93/4/):

我创建了一个名为WatchClickOutside的特殊组件，它可以像这样使用（我假设JSX语法）：

<WatchClickOutside onClickOutside={this.handleClose}>
  <SomeDropdownEtc>
</WatchClickOutside>

以下是WatchClickOutside组件的代码：

import React, { Component } from 'react';

export default class WatchClickOutside extends Component {
  constructor(props) {
    super(props);
    this.handleClick = this.handleClick.bind(this);
  }

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

  componentWillUnmount() {
    // remember to remove all events to avoid memory leaks
    document.body.removeEventListener('click', this.handleClick);
  }

  handleClick(event) {
    const {container} = this.refs; // get container that we'll wait to be clicked outside
    const {onClickOutside} = this.props; // get click outside callback
    const {target} = event; // get direct click event target

    // if there is no proper callback - no point of checking
    if (typeof onClickOutside !== 'function') {
      return;
    }

    // if target is container - container was not clicked outside
    // if container contains clicked target - click was not outside of it
    if (target !== container && !container.contains(target)) {
      onClickOutside(event); // clicked outside - fire callback
    }
  }

  render() {
    return (
      <div ref="container">
        {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;
    }
}