Bootstrap 3导航栏下拉菜单全高

<li class="dropdown">
  <a href="#" class="dropdown-toggle" data-toggle="dropdown" id="dropdownMenu">下拉菜单</a>
  <ul class="dropdown-menu" role="menu" aria-labelledby="dropdownMenu">
    <!-- 下拉菜单项 -->
  </ul>
</li>

<style>
  .dropdown-menu.full-height {
    height: 100vh; /* 设置高度为视口高度 */
    overflow-y: auto; /* 添加滚动条，以适应内容超出屏幕高度的情况 */
  }
</style>

<script>
  $(document).ready(function() {
    $('#dropdownMenu').on('show.bs.dropdown', function() {
      $('.dropdown-menu').addClass('full-height');
    });

    $('#dropdownMenu').on('hide.bs.dropdown', function() {
      $('.dropdown-menu').removeClass('full-height');
    });
  });
</script>