可以为DOM元素设置tabindex。当用户在DOM元素外部单击时，这将触发一个模糊事件。

Demo

<div tabindex="1">
    Focus me
</div>

document.querySelector("div").onblur = function(){
   console.log('clicked outside')
}
document.querySelector("div").onfocus = function(){
   console.log('clicked inside')
}

首先，您必须使用mouseenter和mouseleave事件跟踪鼠标是在元素1内部还是外部。然后，您可以创建一个覆盖整个屏幕的element2来检测任何点击，并根据您是在element1内部还是外部做出相应的反应。

我强烈建议同时处理初始化和清理，出于明显的原因，element2应尽可能临时。

在下面的示例中，覆盖是位于某个位置的元素，可以通过单击内部来选择，也可以通过单击外部来取消选择。_init和_release方法是自动初始化/清理过程的一部分。该类继承自具有内部和外部元素的ClickOverlay，不用担心。我使用了outerElement.parentNode.appendChild来避免冲突。

import ClickOverlay from './ClickOverlay.js'

/* CSS */
// .unselect-helper {
//  position: fixed; left: -100vw; top: -100vh;
//  width: 200vw; height: 200vh;
// }
// .selected {outline: 1px solid black}

export default class ResizeOverlay extends ClickOverlay {
    _init(_opts) {
        this.enterListener = () => this.onEnter()
        this.innerElement.addEventListener('mouseenter', this.enterListener)
        this.leaveListener = () => this.onLeave()
        this.innerElement.addEventListener('mouseleave', this.leaveListener)
        this.selectListener = () => {
            if (this.unselectHelper)
                return
            this.unselectHelper = document.createElement('div')
            this.unselectHelper.classList.add('unselect-helper')
            this.unselectListener = () => {
                if (this.mouseInside)
                    return
                this.clearUnselectHelper()
                this.onUnselect()
            }
            this.unselectHelper.addEventListener('pointerdown'
                , this.unselectListener)
            this.outerElement.parentNode.appendChild(this.unselectHelper)
            this.onSelect()
        }
        this.innerElement.addEventListener('pointerup', this.selectListener)
    }

    _release() {
        this.innerElement.removeEventListener('mouseenter', this.enterListener)
        this.innerElement.removeEventListener('mouseleave', this.leaveListener)
        this.innerElement.removeEventListener('pointerup', this.selectListener)
        this.clearUnselectHelper()
    }

    clearUnselectHelper() {
        if (!this.unselectHelper)
            return
        this.unselectHelper.removeEventListener('pointerdown'
            , this.unselectListener)
        this.unselectHelper.remove()
        delete this.unselectListener
        delete this.unselectHelper
    }

    onEnter() {
        this.mouseInside = true
    }

    onLeave() {
        delete this.mouseInside
    }

    onSelect() {
        this.innerElement.classList.add('selected')
    }

    onUnselect() {
        this.innerElement.classList.remove('selected')
    }
}

$(document).on('click.menu.hide', function(e){
  if ( !$(e.target).closest('#my_menu').length ) {
    $('#my_menu').find('ul').toggleClass('active', false);
  }
});

$(document).on('click.menu.show', '#my_menu li', function(e){
  $(this).find('ul').toggleClass('active');
});

div {
  float: left;
}

ul {
  padding: 0;
  position: relative;
}
ul li {
  padding: 5px 25px 5px 10px;
  border: 1px solid silver;
  cursor: pointer;
  list-style: none;
  margin-top: -1px;
  white-space: nowrap;
}
ul li ul:before {
  margin-right: -20px;
  position: absolute;
  top: -17px;
  right: 0;
  content: "\25BC";
}
ul li ul li {
  visibility: hidden;
  height: 0;
  padding-top: 0;
  padding-bottom: 0;
  border-width: 0 0 1px 0;
}
ul li ul li:last-child {
  border: none;
}
ul li ul.active:before {
  content: "\25B2";
}
ul li ul.active li {
  display: list-item;
  visibility: visible;
  height: inherit;
  padding: 5px 25px 5px 10px;
}

<script src="https://code.jquery.com/jquery-2.1.4.js"></script>
<div>
  <ul id="my_menu">
    <li>Menu 1
      <ul>
        <li>subMenu 1</li>
        <li>subMenu 2</li>
        <li>subMenu 3</li>
        <li>subMenu 4</li>
      </ul>
    </li>
    <li>Menu 2
      <ul>
        <li>subMenu 1</li>
        <li>subMenu 2</li>
        <li>subMenu 3</li>
        <li>subMenu 4</li>
      </ul>
    </li>
    <li>Menu 3</li>
    <li>Menu 4</li>
    <li>Menu 5</li>
    <li>Menu 6</li>
  </ul>
</div>

这里是jsbin版本http://jsbin.com/xopacadeni/edit?html，css，js，输出

这是我解决这个问题的方法：

$(document).ready(function() {
  $('#user-toggle').click(function(e) {
    $('#user-nav').toggle();
    e.stopPropagation();
  });

  $('body').click(function() {
    $('#user-nav').hide(); 
  });

  $('#user-nav').click(function(e){
    e.stopPropagation();
  });
});

我在一些jQuery日历插件中找到了这个方法。

function ClickOutsideCheck(e)
{
  var el = e.target;
  var popup = $('.popup:visible')[0];
  if (popup==undefined)
    return true;

  while (true){
    if (el == popup ) {
      return true;
    } else if (el == document) {
      $(".popup").hide();
      return false;
    } else {
      el = $(el).parent()[0];
    }
  }
};

$(document).bind('mousedown.popup', ClickOutsideCheck);

这对我来说很好。我不是专家。

$(document).click(function(event) {
  var $target = $(event.target);
  if(!$target.closest('#hamburger, a').length &&
  $('#hamburger, a').is(":visible")) {
    $('nav').slideToggle();
  }
});