element ui 侧边导航点击后直接就新页面了

点击菜单之后正常应该是main部分更新,但是他现在整个页面跳转了。

<template>
<el-container style="height:100%">
      <el-header style="height:60px;padding:0;display:flex;justify-content:flex-start;"></el-header>
      <el-container>
        <el-aside width="200px">
          <el-row class="tac">
            <el-col :span="24">
              <el-menu
                :default-active="this.$route.path"
                class="el-menu-vertical-demo"
                router     
              >
                <el-menu-item-group>
                  <el-menu-item index="/welcome" style="text-align:start;">首页</el-menu-item> 
                </el-menu-item-group>
                <el-submenu index="1">    
                  <template slot="title">
                    <!-- <i class="el-icon-location"></i> -->
                    <span>aaa</span>
                  </template>
                  <el-menu-item-group>
                    <el-menu-item index="/cont">一览</el-menu-item> 
                  </el-menu-item-group>
                </el-submenu>
                <el-submenu index="2">
                  <template slot="title">
                    <!-- <i class="el-icon-location"></i> -->
                    <span>bbb</span>
                  </template>
                  <el-menu-item-group>
                    <el-menu-item index="/invo">bbb_1</el-menu-item>
                    <el-menu-item index="/tick">bbb_2</el-menu-item>
                  </el-menu-item-group>
                </el-submenu>
              </el-menu>
            </el-col>
          </el-row>
        </el-aside>
        <el-main style="padding:24px;">
          <router-view></router-view>
        </el-main>
      </el-container>
    </el-container>

   </template>
   

贴出代码看看呢,你是怎么写的
或参考下
https://blog.csdn.net/m0_46309087/article/details/119701254