1、router.js（路由）

//主要部分
meta:{ keepAlive: true}

import myDemand from '../views/keep/myDemand.vue'
import AboutView from '../views/keep/AboutView.vue'
const routes = [
  {
    path: '/myDemand',
    name: 'myDemand',
    meta:{
      keepAlive: true,
    },
    component: myDemand
  },
  {
    path: '/AboutView',
    name: 'AboutView',
    component: AboutView
  },
]

2、HomeView.vue （主页）

//主要部分
<keep-alive>
  <router-view v-if="$route.meta.keepAlive"></router-view>
</keep-alive>
<router-view v-if="!$route.meta.keepAlive"></router-view>

//完整代码
<template>
  <el-container>
    <el-aside width="200px">
      <el-menu class="el-menu-vertical-demo" @select="handleSelect" background-color="#ccc" text-color="#000"
        active-text-color="#000">
        <el-menu-item index="myDemand">
          <span slot="title">导航一</span>
        </el-menu-item>
        <el-menu-item index="AboutView">
          <span slot="title">导航二</span>
        </el-menu-item>
      </el-menu>
    </el-aside>
    <el-main>
      <keep-alive>
        <router-view v-if="$route.meta.keepAlive"></router-view>
      </keep-alive>
      <router-view v-if="!$route.meta.keepAlive"></router-view>
    </el-main>
  </el-container>
</template>

<script>
export default {
  name: 'HomeView',
  components: {},
  data () {
    return {}
  },
  methods: {
    handleSelect (key) {
      this.$router.push({ path: `/${key}` })
    }
  }
}
</script>
<style lang='less' scoped>
.el-container {
  height: 100%;

  .el-aside {
    background-color: #D3DCE6;
    color: #333;
    text-align: center;
    line-height: 200px;
    height: 100%;

    .el-menu {
      height: 100%;
    }
  }
}
</style>

3、myDemand.vue (有缓存页面)

<template>
  <div>
    <el-row>
      <el-col :span="4">
        <el-input v-model="input" placeholder="请输入内容"></el-input>
      </el-col>
      <el-col :span="12">
        <el-select v-model="value" placeholder="请选择">
          <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value">
          </el-option>
        </el-select>
      </el-col>
      <el-button type="primary">搜索</el-button>
    </el-row>
  </div>
</template>

<script>
export default {
  name: 'myDemand',
  components: {},
  data () {
    return {
      input: '',
      options: [{
        value: '选项1',
        label: '黄金糕'
      }, {
        value: '选项2',
        label: '双皮奶'
      }],
      value: '',
    }
  },
  activated () {
    // 页面激活后的钩子函数，一进入页面就触发，如果想进入页面重新请求写在该钩子中
    console.log("测试")
    // equipmentType(this, {})
    //   .then((res) => {
    //     if (res.status === 1) {
          let history = this.input;
          this.input = '';
          this.$nextTick(() => {
            this.input = history
          })
      //   }
      // }).finally(() => {
      //   this.searchLoading = false;
      // });

  },
}
</script>
<style>
.el-table {
  margin-top: 50px;
}
</style>

4、AboutView.vue（无缓存页面）

<template>
  <div class="about">
    <h1>This is an about page</h1>
    <el-input v-model="input" placeholder="请输入内容"></el-input>
  </div>
</template>
<script>
export default {
  data () {
    return {
      input: ''
    }
  }
}
</script>