bootstrap菜单展开收起_Bootstrap之侧边导航菜单(可折叠分组)

Bootstrap的侧边导航菜单可以通过添加collapse插件实现折叠展开的效果。以下是一个基本的示例：

<div class="container-fluid">
  <div class="row">
    <nav class="col-md-2 d-none d-md-block bg-light sidebar">
      <div class="sidebar-sticky">
        <ul class="nav flex-column">
          <li class="nav-item">
            <a class="nav-link active" href="#">
              <span data-feather="home"></span>
              Dashboard <span class="sr-only">(current)</span>
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="#">
              <span data-feather="file"></span>
              Orders
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="#">
              <span data-feather="shopping-cart"></span>
              Products
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="#">
              <span data-feather="users"></span>
              Customers
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="#">
              <span data-feather="bar-chart-2"></span>
              Reports
            </a>
          </li>
          <li class="nav-item">
            <a class="nav-link" href="#">
              <span data-feather="layers"></span>
              Integrations
            </a>
          </li>
        </ul>
      </div>
    </nav>

    <main role="main" class="col-md-9 ml-sm-auto col-lg-10 pt-3 px-4">
      <div class="d-flex justify-content-between flex-wrap flex-md-nowrap align-items-center pb-2 mb-3 border-bottom">
        <h1 class="h2">Dashboard</h1>
        <div class="btn-toolbar mb-2 mb-md-0">
          <div class="btn-group mr-2">
            <button class="btn btn-sm btn-outline-secondary">Share</button>
            <button class="btn btn-sm btn-outline-secondary">Export</button>
          </div>
          <button class="btn btn-sm btn-outline-secondary dropdown-toggle">
            <span data-feather="calendar"></span>
            This week
          </button>
        </div>
      </div>

      <canvas class="my-4 w-100" id="myChart" width="900" height="380"></canvas>

      <h2>Section title</h2>
      <div class="table-responsive">
        <table class="table table-striped table-sm">
          <thead>
            <tr>
              <th>#</th>
              <th>Header</th>
              <th>Header</th>
              <th>Header</th>
              <th>Header</th>
            </tr>
          </thead>
          <tbody>
            <tr>
              <td>1,001</td>
              <td>Lorem</td>
              <td>ipsum</td>
              <td>dolor</td>
              <td>sit</td>
            </tr>
            <tr>
              <td>1,002</td>
              <td>amet</td>
              <td>consectetur</td>
              <td>adipiscing</td>
              <td>elit</td>
            </tr>
            <tr>
              <td>1,003</td>
              <td>Integer</td>
              <td>nec</td>
              <td>odio</td>
              <td>Praesent</td>
            </tr>
          </tbody>
        </table>
      </div>
    </main>
  </div>
</div>

在此示例中，侧边栏导航菜单包含一个`ul`元素，其中每个`li`元素都包含一个`a`元素，用于显示菜单项。当菜单项被点击时，页面右侧的主要内容区域将相应地更新。

要实现折叠效果，我们可以使用Bootstrap的collapse插件。将`ul`元素包装在一个具有`collapse`类的`div`元素中，并将`data-toggle`和`data-target`属性添加到一个控件元素，例如`<a>`或`<button>`。在此示例中，我们将`data-toggle`属性设置为`collapse`，将`data-target`属性设置为`#sidebar`，该元素的ID为`sidebar`。这将使侧边栏导航菜单在点击控件元素时展开或折叠。

<nav class="col-md-2 d-none d-md-block bg-light sidebar">
  <div class="sidebar-sticky">
    <ul class="nav flex-column">
      <li class="nav-item">
        <a class="nav-link active" href="#">
          <span data-feather="home"></span>
          Dashboard <span class="sr-only">(current)</span>
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">
          <span data-feather="file"></span>
          Orders
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">
          <span data-feather="shopping-cart"></span>
          Products
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">
          <span data-feather="users"></span>
          Customers
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">
          <span data-feather="bar-chart-2"></span>
          Reports
        </a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">
          <span data-feather="layers"></span>
          Integrations
        </a>
      </li>
    </ul>
  </div>
</nav>

<button class="btn btn-sm btn-outline-secondary d-md-none" type="button" data-toggle="collapse" data-target="#sidebar" aria-controls="sidebar" aria-expanded="false" aria-label="Toggle navigation">
  <span data-feather="menu"></span>
</button>

在上面的代码中，我们还添加了一个用于在小屏幕上折叠导航菜单的按钮。当屏幕宽度小于`md`时，导航菜单将被折叠，并且按钮将显示在页面顶部。单击按钮将展开或折叠导航菜单。

希望这可以回答你的问题！