element-ui中Menu三级菜单嵌套

    <!-- 侧边栏 -->
          <el-menu router unique-opened>
            <div v-for="(item1, index) in menuList" :key="index">
              <!-- 一级菜单（没有任何子级菜单）-->
              <el-menu-item :index="item1.jump" v-if="!item1.list">{{
                item1.title
              }}</el-menu-item>
              <!-- 一级菜单（有子级菜单）-->
              <el-submenu :index="item1.jump" v-else>
                <template slot="title">{{ item1.title }}</template>

                <!-- 遍历二级菜单容器 -->
                <div v-for="(item2, index) in item1.list" :key="index">
                  <!-- 判断二级菜单（没有三级菜单）-->
                  <el-menu-item :index="item2.jump" v-if="!item2.list">{{
                    item2.title
                  }}</el-menu-item>

                  <!-- 判断二级菜单（有三级菜单）-->
                  <el-submenu :index="item2.jump" v-if="item2.list">
                    <template slot="title">{{ item2.title }}</template>
                    <el-menu-item
                      :index="item3.jump"
                      v-for="(item3, index) in item2.list"
                      :key="index"
                      >{{ item3.title }}
                    </el-menu-item>
                  </el-submenu>
                </div>
              </el-submenu>
            </div>
          </el-menu>
          <!-- /侧边栏 -->

实现效果：