环境

windows: 10
vue-cli: 4
编辑器： vsCode
npm: 6.11.3 ＃去nodejs网安装 
http://nodejs.cn/download/

https://npm.taobao.org/mirrors/node/v12.12.0/node-v12.12.0-x64.msi

１．安装 ：

>npm install -g @vue/cli
# 查看版本
PS D:\vue\project-3> vue -V
@vue/cli 4.0.4

２．创建项目：

添加淘宝镜像：
npm install -g cnpm --registry=https://registry.npm.taobao.org
创建项目
vue create project-3

#这里可以上下选择， 我们选 手动
Vue CLI v4.0.4
? Please pick a preset:    
  default (babel, eslint)  
> Manually select features 

# 然后根据自己的需求选组件
Vue CLI v4.0.4
? Please pick a preset: Manually select features
? Check the features needed for your project: 
 (*) Babel
 ( ) TypeScript
 ( ) Progressive Web App (PWA) Support        
 (*) Router
 (*) Vuex
 (*) CSS Pre-processors
>(*) Linter / Formatter
 ( ) Unit Testing
 ( ) E2E Testing

３．创建路由

3.1 在{项目路径}/src/router/index.js中添加一路由

3.2 在App.vue 中添加 <router-link to="/demo1">Demo1</router-link>

<template>
  <div id="app">
    <div id="nav">
      <router-link to="/">Home</router-link> |
      <router-link to="/about">About</router-link> |
      <router-link to="/demo1">Demo1</router-link>
    </div>
    <router-view/>
  </div>
</template>

<style lang="less">
#app {
  font-family: 'Avenir', Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
}

#nav {
  padding: 30px;

  a {
    font-weight: bold;
    color: #2c3e50;

    &.router-link-exact-active {
      color: #42b983;
    }
  }
}
</style>

3.3 创建 Demo1.vue

<template>
  <div class="test">
    <h1>This is an Demo1 page</h1>

  </div>

</template>

<script>
</script>

<style lang="">
  
</style>

3.4 运行项目

>npm run serve

 DONE  Compiled successfully in 3656ms                                                    11:20:07

  App running at:
  - Local:   http://localhost:8080/
  - Network: http://192.168.1.105:8080/

  Note that the development build is not optimized.
  To create a production build, run npm run build. 

3.5 测试，访问 http://localhost:8080/demo1