I downloaded it several times because I didn’t understand that the official website node I downloaded at the beginning needs to be uninstalled and then installed nvm. I downloaded node through nvm, and when I used nvm, I kept wondering why node -v and npm -v They are not internal commands. It turned out that I did not have nvm on to start nvm to manage him. After starting it, it succeeded:
node -v //查看node版本号
npm -v //查看npm是不是也安装成功
nvm on //启用nvm管理工具
nvm list //看nvm里面的node版本数
nvm use 版本号 //切换Node版本
