css – Bootstrap 4 Dropdown – 禁用popper.js导致的自动放置

我正在使用Bootstrap 4下拉菜单,大约有18个下拉项目.
由于高度太高,popper.js会自动将下拉列表从其原始位置移动到屏幕顶部.我该如何防止这种情况？
我总是希望下拉菜单显示在切换它的按钮下方.
谢谢

按要求发布代码 – (我正在使用C#,但代码应传达我希望的观点)

<div class="dropdown">
                <span class="p-2 text-uppercase font-weight-semi-bold pointer dropdown-toggle" href="#" role="button" id="dropdownMenuLink" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
                    @topMenu.Name
                </span>
                <div class="dropdown-menu"  style="font-size:0.9rem" aria-labelledby="dropdownMenuButton">
                    @foreach (var subMenu in topMenu.SubMenu)
                    {
                        <a class="dropdown-item" href="@Url.Content("~/" + subMenu.Url)">@subMenu.Name</a>

                    }
                </div>
            </div>

解决方法

Bootstrap 4.1

有一个新的“显示”选项,禁用popper.js下拉定位.使用data-display =“static”到prevent popper.js from dynamically changing the dropdown position ……

Bootstrap 4.0

popper.js和定位存在一些问题.

我发现解决方案是相对于.dropdown定位,并在下拉切换中将其设置为data-boundary =“”选项：
https://www.codeply.com/go/zZJwAuwC5s

<div class="dropdown position-relative" id="dd">
        <button type="button" data-boundary="dd" class="btn btn-primary dropdown-toggle" data-toggle="dropdown">
            Dropdown
        </button>
        <div class="dropdown-menu">
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            <a class="dropdown-item" href="#">Link 1</a>
            ...
        </div>
   </div>

边界设置为下拉列表的ID.了解更多关于data-boundary.

相关问题：
Bootstrap 4: Why popover inside scrollable dropdown doesn’t show?
Scrolling a dropdown in a modal in Bootstrap4