【Vue报错】app.js:167 Uncaught TypeError: Cannot read properties of undefined (reading ‘install‘)

背景：

控制台报错

app.js:167 Uncaught TypeError: Cannot read properties of undefined (reading 'install')
    at Function.Vue.use (vue.runtime.esm.js?c320:5739:1)
    at eval (index.js?5aa4:19:1)
    at Module../src/router/index.js (app.js:95:1)
    at __webpack_require__ (app.js:164:33)
    at fn (app.js:420:21)
    at eval (main.js:4:65)
    at Module../src/main.js (app.js:85:1)
    at __webpack_require__ (app.js:164:33)
    at app.js:1345:109
    at Function.__webpack_require__.O (app.js:210:23)

解决方法 ：

1.找到报错文件，router/index.js，发现运行正常，但是控制台报错，并且原来渲染ok的页面也变成空白了

2.求助百度 说是这个报错是router版本过高，导致跟vue2项目不匹配，检查下