在 ASP.Net Core Web 应用程序（引导程序）中向导航栏添加下拉菜单

Posted 2023-03-27

【中文标题】在 ASP.Net Core Web 应用程序（引导程序）中向导航栏添加下拉菜单

【英文标题】：Adding a Dropdown menu to the NavBar in an ASP.Net Core Web App (bootstrap)

【发布时间】：2021-11-22 17:15:38

【问题描述】：

在 Visual Studio 中，我创建了一个新的 ASP.Net Core Web App

然后我添加一个下拉菜单（根据 Bootstrap 文档） https://getbootstrap.com/docs/5.1/components/navbar/

html 代码的标头部分如下所示：

<header>
    <nav class="navbar navbar-expand-sm navbar-toggleable-sm navbar-light bg-white border-bottom box-shadow mb-3">
        <div class="container">
            <a class="navbar-brand" asp-area="" asp-page="/Index">WebApplication1</a>
            <button class="navbar-toggler" type="button" data-toggle="collapse" data-target=".navbar-collapse" aria-controls="navbarSupportedContent"
                    aria-expanded="false" aria-label="Toggle navigation">
                <span class="navbar-toggler-icon"></span>
            </button>
            <div class="navbar-collapse collapse d-sm-inline-flex flex-sm-row-reverse">
                <ul class="navbar-nav flex-grow-1">
                    <li class="nav-item">
                        <a class="nav-link text-dark" asp-area="" asp-page="/Index">Home</a>
                    </li>
                    <li class="nav-item">
                        <a class="nav-link text-dark" asp-area="" asp-page="/Privacy">Privacy</a>
                    </li>
                    <li class="nav-item dropdown">
                      <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
                        Dropdown
                      </a>
                      <ul class="dropdown-menu" aria-labelledby="navbarDropdown">
                        <li><a class="dropdown-item" href="#">Action</a></li>
                        <li><a class="dropdown-item" href="#">Another action</a></li>
                        <li><hr class="dropdown-divider"></li>
                        <li><a class="dropdown-item" href="#">Something else here</a></li>
                      </ul>
                    </li>
                </ul>
            </div>
        </div>
    </nav>
</header>

但下拉菜单不起作用。当我单击它时，不会出现下拉菜单： https://i.stack.imgur.com/szrE4.png

【参考方案1】：

确保你的Bootstrap版本是v5.1，你可以在你的项目_Layout.cshtml添加如下css和js文件：

<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/bootstrap/5.1.1/css/bootstrap.min.css" integrity="sha512-6KY5s6UI5J7SVYuZB4S/CZMyPylqyyNZco376NM2Z8Sb8OxEdp02e1jkKk/wZxIEmjQ6DRCEBhni+gpr9c4tvA==" crossorigin="anonymous" referrerpolicy="no-referrer" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/bootstrap/5.1.1/js/bootstrap.min.js" integrity="sha512-ewfXo9Gq53e1q1+WDTjaHAGZ8UvCWq0eXONhwDuIoaH8xz2r96uoAYaQCm1oQhnBfRXrvJztNXFsTloJfgbL5Q==" crossorigin="anonymous" referrerpolicy="no-referrer"></script>

对于 Bootstrap v4.x，您需要将代码更改为：

<li class="nav-item dropdown">
        <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
            Dropdown
        </a>
        <div class="dropdown-menu" aria-labelledby="navbarDropdown">
            <a class="dropdown-item" href="#">Action</a>
            <a class="dropdown-item" href="#">Another action</a>
            <div class="dropdown-divider"></div>
            <a class="dropdown-item" href="#">Something else here</a>
        </div>
</li>

【讨论】：

Rena，您的 v4.x 答案运行良好。我正在使用 Visual Studio 2019，其默认的 DotNet Core 应用似乎使用 v4.3.1：（根据 bootstrap.js）Bootstrap v4.3.1