通过组件slot来设置下拉触发的元素以及需要通过具名slot为dropdown 来设置下拉菜单。默认情况下，下拉按钮只要hover即可，无需点击也会显示下拉菜单。

<el-dropdown>
  <span class="el-dropdown-link">
    下拉菜单<i class="el-icon-arrow-down el-icon--right"></i>
  </span>
  <el-dropdown-menu slot="dropdown">
    <el-dropdown-item>黄金糕</el-dropdown-item>
    <el-dropdown-item>狮子头</el-dropdown-item>
    <el-dropdown-item>螺蛳粉</el-dropdown-item>
    <el-dropdown-item disabled>双皮奶</el-dropdown-item>
    <el-dropdown-item divided>蚵仔煎</el-dropdown-item>
  </el-dropdown-menu>
</el-dropdown>

可以配置 click 激活或者 hover 激活。

<el-dropdown trigger="click">
      <span class="el-dropdown-link">
        下拉菜单<i class="el-icon-arrow-down el-icon--right"></i>
      </span>
      <el-dropdown-menu slot="dropdown">
        <el-dropdown-item icon="el-icon-plus">黄金糕</el-dropdown-item>
        <el-dropdown-item icon="el-icon-circle-plus">狮子头</el-dropdown-item>
        <el-dropdown-item icon="el-icon-circle-plus-outline">螺蛳粉</el-dropdown-item>
        <el-dropdown-item icon="el-icon-check">双皮奶</el-dropdown-item>
        <el-dropdown-item icon="el-icon-circle-check">蚵仔煎</el-dropdown-item>
      </el-dropdown-menu>
    </el-dropdown>

本项目中使用el-dropdown：

<el-dropdown class="avatar-container" trigger="click">
      <div class="avatar-wrapper">
        <i class="el-icon-user-solid" style="font-weight: 600"/>
        欢迎您 {{ chinaName }}
        <i class="el-icon-caret-bottom"/>
      </div>
      <el-dropdown-menu slot="dropdown" class="user-dropdown">
        <router-link class="inlineBlock" to="/">
          <el-dropdown-item>
            首页
          </el-dropdown-item>
        </router-link>
        <el-dropdown-item divided>
          <span style="display:block;" @click="logout">退出</span>
        </el-dropdown-item>
      </el-dropdown-menu>
    </el-dropdown>

divided:显示分割线。