您可以通过下面的代码来解决这个问题。

$(document).on('click.bs.dropdown.data-api', '.keep_it_open', function (e) { e.stopPropagation(); }); <link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css" rel="stylesheet"/> <meta name="viewport" content="width=device-width, initial-scale=1"> <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js"></script> <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css"> <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script> <div class="dropdown keep_it_open"> <button class="btn btn-primary dropdown-toggle" type="button" data-toggle="dropdown">Dropdown Example <span class="caret"></span></button> <ul class="dropdown-menu"> <li><a href="#">HTML</a></li> <li><a href="#">CSS</a></li> <li><a href="#">JavaScript</a></li> </ul> </div>

比如Bootstrap 4 Alpha有这个菜单事件。为什么不用呢?

// PREVENT INSIDE MEGA DROPDOWN
$('.dropdown-menu').on("click.bs.dropdown", function (e) {
    e.stopPropagation();
    e.preventDefault();                
});

我修改了@Vartan的答案，使它与Bootstrap 4.3一起工作。他的解决方案不再适用于最新版本，因为目标属性总是返回下拉菜单的根div，无论单击放在哪里。

代码如下:

$('.dropdown-keep-open').on('hide.bs.dropdown', function (e) {
  if (!e.clickEvent) {
    // There is no `clickEvent` property in the `e` object when the `button` (or any other trigger) is clicked. 
    // What we usually want to happen in such situations is to hide the dropdown so we let it hide. 
    return true;
  }

  var target = $(e.clickEvent.target);

  return !(target.hasClass('dropdown-keep-open') || target.parents('.dropdown-keep-open').length);
});

<div class="dropdown dropdown-keep-open">
  <button class="btn btn-secondary dropdown-toggle" type="button" id="dropdownMenuButton" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    Dropdown button
  </button>
  <div class="dropdown-menu" aria-labelledby="dropdownMenuButton">
    <a class="dropdown-item" href="#">Action</a>
    <a class="dropdown-item" href="#">Another action</a>
    <a class="dropdown-item" href="#">Something else here</a>
  </div>
</div>

Bootstrap已经解决了这个问题，他们在下拉菜单中支持<form>标签。他们的解决方案很容易理解，你可以在这里阅读:https://github.com/twbs/bootstrap/blob/v4-dev/js/src/dropdown.js

这可以归结为在文档元素上阻止传播，并且只对click.bs.dropdown类型的事件这样做。Data-api '匹配选择器'。下拉.your-custom-class-for-keep-open-on-click-elements”。

或者在代码中

$(document).on('click.bs.dropdown.data-api', '.dropdown .keep-open-on-click', (event) => {
    event.stopPropagation();
});

我还找到了一个解决办法。

假设Twitter Bootstrap Components相关事件处理程序被委托给文档对象，我循环所附的处理程序，并检查当前单击的元素(或其父元素之一)是否与委托的事件有关。

$('ul.dropdown-menu.mega-dropdown-menu').on('click', function(event){
    var events = $._data(document, 'events') || {};
    events = events.click || [];
    for(var i = 0; i < events.length; i++) {
        if(events[i].selector) {

            //Check if the clicked element matches the event selector
            if($(event.target).is(events[i].selector)) {
                events[i].handler.call(event.target, event);
            }

            // Check if any of the clicked element parents matches the 
            // delegated event selector (Emulating propagation)
            $(event.target).parents(events[i].selector).each(function(){
                events[i].handler.call(this, event);
            });
        }
    }
    event.stopPropagation(); //Always stop propagation
});

希望它能帮助任何寻求类似解决方案的人。

谢谢大家的帮助。

如果使用return false或stopPropagation()方法，您可能会遇到一些问题，因为您的事件将被中断。 试试这段代码，它的工作很好:

$(function() {
    $('.dropdown').on("click", function (e) {
            $('.keep-open').removeClass("show");
    });
    $('.dropdown-toggle').on("click", function () {
            $('.keep-open').addClass("show");
    });

    $( ".closeDropdown" ).click(function() {
        $('.dropdown').closeDropdown();
    });
});
jQuery.fn.extend({
    closeDropdown: function() {
        this.addClass('show')
            .removeClass("keep-open")
            .click()
            .addClass("keep-open");
    }
  });

在HTML中:

<div class="dropdown keep-open" id="search-menu" >
    <button  class="btn dropdown-toggle btn  btn-primary" type="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
    <i class="fa fa-filter fa-fw"></i> 
    </button>
    <div class="dropdown-menu">
        <button class="dropdown-item" id="opt1" type="button">Option 1</button>
        <button class="dropdown-item" id="opt2" type="button">Option 2</button>
        <button type="button" class="btn btn-primary closeDropdown">Close</button>
    </div>
</div>

如果你想关闭dropdrown:

`$('#search-menu').closeDropdown();`