如果您想使用这个功能已经存在的一个小组件（466字节gzip），那么您可以查看这个库react outclick。

该库的好处在于它还允许您检测组件外部和另一个组件内部的单击。它还支持检测其他类型的事件。

https://stackoverflow.com/a/42234988/9536897解决方案在手机上不起作用。

您可以尝试：

  // returns true if the element or one of its parents has the class classname
  hasSomeParentTheClass(element, classname) {
    if(element.target)
    element=element.target;
    
    if (element.className&& element.className.split(" ").indexOf(classname) >= 0) return true;
    return (
      element.parentNode &&
      this.hasSomeParentTheClass(element.parentNode, classname)
    );
  }

  componentDidMount() {
    const fthis = this;

    $(window).click(function (element) {
      if (!fthis.hasSomeParentTheClass(element, "myClass"))
        fthis.setState({ pharmacyFocus: null });
    });
  }

在视图中，将className赋给特定元素。

非侵入性方式无需添加另一个DIV EL。

注意：React可能会说findDomNode已弃用，但到目前为止，我还没有遇到任何问题

@异常：单击要忽略的类

@idException:单击时忽略的id

import React from "react"
import ReactDOM from "react-dom"
type Func1<T1, R> = (a1: T1) => R


export function closest(
    el: Element,
    fn: (el: Element) => boolean
  ): Element | undefined {
    let el_: Element | null = el;
  
    while (el_) {
      if (fn(el_)) {
        return el_;
      }
  
      el_ = el_.parentElement;
    }
  }
let instances: ClickOutside[] = []

type Props = {
  idException?: string,
  exceptions?: (string | Func1<MouseEvent, boolean>)[]
  handleClickOutside: Func1<MouseEvent, void>

}


export default class ClickOutside extends React.Component<Props> {
  static defaultProps = {
    exceptions: []
  };

  componentDidMount() {
    if (instances.length === 0) {
      document.addEventListener("mousedown", this.handleAll, true)
      window.parent.document.addEventListener(
        "mousedown",
        this.handleAll,
        true
      )
    }
    instances.push(this)
  }

  componentWillUnmount() {
    instances.splice(instances.indexOf(this), 1)
    if (instances.length === 0) {
      document.removeEventListener("mousedown", this.handleAll, true)
      window.parent.document.removeEventListener(
        "mousedown",
        this.handleAll,
        true
      )
    }
  }

  handleAll = (e: MouseEvent) => {

    const target: HTMLElement = e.target as HTMLElement
    if (!target) return

    instances.forEach(instance => {
      const { exceptions, handleClickOutside: onClickOutside, idException } = instance.props as Required<Props>
      let exceptionsCount = 0

      if (exceptions.length > 0) {
        const { functionExceptions, stringExceptions } = exceptions.reduce(
          (acc, exception) => {
            switch (typeof exception) {
              case "function":
                acc.functionExceptions.push(exception)
                break
              case "string":
                acc.stringExceptions.push(exception)
                break
            }

            return acc
          },
          { functionExceptions: [] as Func1<MouseEvent, boolean>[], stringExceptions: [] as string[] }
        )
        if (functionExceptions.length > 0) {
          exceptionsCount += functionExceptions.filter(
            exception => exception(e) === true
          ).length
        }

        if (exceptionsCount === 0 && stringExceptions.length > 0) {

          const el = closest(target, (e) => stringExceptions.some(ex => e.classList.contains(ex)))
          if (el) {
            exceptionsCount++
          }
        }
      }

      if (idException) {
        const target = e.target as HTMLDivElement
        if (document.getElementById(idException)!.contains(target)) {
          exceptionsCount++
        }
      }

      if (exceptionsCount === 0) {
        // eslint-disable-next-line react/no-find-dom-node
        const node = ReactDOM.findDOMNode(instance)

        if (node && !node.contains(target)) {
          onClickOutside(e)
        }
      }
    })
  };

  render() {
    return React.Children.only(this.props.children)
  }
}

用法

<ClickOutside {...{ handleClickOutside: () => { alert('Clicked Outside') } }}>
    <div >
        <div>Breathe</div>
    </div>
</ClickOutside>

您只需在主体上安装一个双击处理程序，并在此元素上安装另一个。在该元素的处理程序中，只需返回false以防止事件传播。因此，当双击发生时，如果它在元素上，它将被捕获，并且不会传播到主体上的处理程序。否则它会被身体上的处理程序抓住。

更新：如果你真的不想阻止事件传播，你只需要使用closest来检查点击是发生在你的元素还是他的一个孩子身上：

<html>
<head>
<script src="https://code.jquery.com/jquery-2.1.4.min.js"></script>
<script>
$(document).on('click', function(event) {
    if (!$(event.target).closest('#div3').length) {
    alert("outside");
    }
});
</script>
</head>
<body>
    <div style="background-color:blue;width:100px;height:100px;" id="div1"></div>
    <div style="background-color:red;width:100px;height:100px;" id="div2"></div>
    <div style="background-color:green;width:100px;height:100px;" id="div3"></div>
    <div style="background-color:yellow;width:100px;height:100px;" id="div4"></div>
    <div style="background-color:grey;width:100px;height:100px;" id="div5"></div>
</body>
</html>

更新：不带jQuery:

<html>
<head>
<script>
function findClosest (element, fn) {
  if (!element) return undefined;
  return fn(element) ? element : findClosest(element.parentElement, fn);
}
document.addEventListener("click", function(event) {
    var target = findClosest(event.target, function(el) {
        return el.id == 'div3'
    });
    if (!target) {
        alert("outside");
    }
}, false);
</script>
</head>
<body>
    <div style="background-color:blue;width:100px;height:100px;" id="div1"></div>
    <div style="background-color:red;width:100px;height:100px;" id="div2"></div>
    <div style="background-color:green;width:100px;height:100px;" id="div3">
        <div style="background-color:pink;width:50px;height:50px;" id="div6"></div>
    </div>
    <div style="background-color:yellow;width:100px;height:100px;" id="div4"></div>
    <div style="background-color:grey;width:100px;height:100px;" id="div5"></div>
</body>
</html>

如果您需要typescript版本：

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

interface Props {
  ref: React.MutableRefObject<any>;

}

export const useOutsideAlerter = ({ ref }: Props) => {
  useEffect(() => {
    const handleClickOutside = (event: MouseEvent) => {
      if (ref.current && !ref.current.contains(event.target as Node)) {
       //do what ever you want
      }
    };
    // Bind the event listener
    document.addEventListener("mousedown", handleClickOutside);
    return () => {
      // Unbind the event listener on clean up
      document.removeEventListener("mousedown", handleClickOutside);
    };
  }, [ref]);
};
export default useOutsideAlerter;

如果您想扩展它以关闭模态或隐藏某些内容，也可以执行以下操作：

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

interface Props {
  ref: React.MutableRefObject<any>;
  setter: React.Dispatch<React.SetStateAction<boolean>>;
}

export const useOutsideAlerter = ({ ref, setter }: Props) => {
  useEffect(() => {
    const handleClickOutside = (event: MouseEvent) => {
      if (ref.current && !ref.current.contains(event.target as Node)) {
        setter(false);
      }
    };
    // Bind the event listener
    document.addEventListener("mousedown", handleClickOutside);
    return () => {
      // Unbind the event listener on clean up
      document.removeEventListener("mousedown", handleClickOutside);
    };
  }, [ref, setter]);
};
export default useOutsideAlerter;

在我的DROPDOWN案例中，Ben Bud的解决方案工作得很好，但我有一个单独的切换按钮和一个onClick处理程序。因此，外部单击逻辑与单击切换按钮冲突。下面是我如何通过传递按钮的ref来解决这个问题：

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

/**
 * Hook that triggers onClose when clicked outside of ref and buttonRef elements
 */
function useOutsideClicker(ref, buttonRef, onOutsideClick) {
  useEffect(() => {

    function handleClickOutside(event) {
      /* clicked on the element itself */
      if (ref.current && !ref.current.contains(event.target)) {
        return;
      }

      /* clicked on the toggle button */
      if (buttonRef.current && !buttonRef.current.contains(event.target)) {
        return;
      }

      /* If it's something else, trigger onClose */
      onOutsideClick();
    }

    // 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 DropdownMenu(props) {
  const wrapperRef = useRef(null);
  const buttonRef = useRef(null);
  const [dropdownVisible, setDropdownVisible] = useState(false);

  useOutsideClicker(wrapperRef, buttonRef, closeDropdown);

  const toggleDropdown = () => setDropdownVisible(visible => !visible);

  const closeDropdown = () => setDropdownVisible(false);

  return (
    <div>
      <button onClick={toggleDropdown} ref={buttonRef}>Dropdown Toggler</button>
      {dropdownVisible && <div ref={wrapperRef}>{props.children}</div>}
    </div>
  );
}