为什么打开项目目录后“离子服务”无法运行？

Question

It doesn't work as an internal or external system command, once I open up my project directory to run "ionic serve". Even though "ionic" is recognized as a system command. I have searched the internet but haven't found an answer yet that solves the problem.

Answer 1

尝试使用选项“ -g”进行全局安装：npm install -g ionic或npm install -g cordova

Answer 2

Delete data out of the cache folder, update npm and then install Ionic/Cordova. After that try to run ionic serve .

npm cache clean
npm update -g
npm install -g ionic cordova