node -v

npm -v

npm list -g --depth=0

npm config set proxy=http://127.0.0.1:8087
npm config 
set
proxy http:
//username
:password@server:port
npm config 
set
https-proxy http:
//username
:pawword@server:port
npm config set registry=http://registry.npmjs.org

npm config set registry=http://registry.cnpmjs.org

npm config delete proxy

npm config  list