Vue packages version mismatch:
- vue@2.6.10 (D:\0527vue-admin-template\node_modules\vue\dist\vue.runtime.common.js)
- vue-template-compiler@2.7.16 (D:\0527vue-admin-template\node_modules\vue-template-compiler\package.json)
This may cause things to work incorrectly. Make sure to use the same version for both.
If you are using vue-loader@>=10.0, simply update vue-template-compiler.
If you are using vue-loader@<10.0 or vueify, re-installing vue-loader/vueify should bump vue-template-compiler to the latest.

npm 查看vue-loader版本号：

npm list vue-loader

D:\0527vue-admin-template>npm list vue-loader
npm WARN config global `--global`, `--local` are deprecated. Use `--location=global` instead.
knife4j-vue@0.1.0 D:\hikvision_project\0527vue-admin-template
`-- @vue/cli-service@4.5.19
  `-- vue-loader@15.11.1

解决方案：package.json中更改vue-template-compiler与vue版本保持一致：

// 改之前：
//dpendencies:
"vue": "2.6.10",
//devDependencies:
"vue-template-compiler": "^2.6.14",
// 改之后
//dpendencies:
"vue": "2.6.10",
//devDependencies:
"vue-template-compiler": "2.6.10",