'vue-cli-service' 不是内部或外部命令，也不是可运行的程序

npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! app@0.1.0 dev: vue-cli-service serve --mode dev
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the app@0.1.0 dev script.
npm ERR! This is probably not a problem with npm. There is likely additional log
ging output above.
npm WARN Local package.json exists, but node_modules missing, did you mean to in
stall?

npm ERR! A complete log of this run can be found in:
npm ERR! C:UsersAdministratorAppDataRoamingnpm-cache_logs2018-12-05T0
8_48_29_573Z-debug.log