In Angular4 this will work the same. If you get an error I think your problem is somewhere else.
In command prompt type
ng generate component YOURCOMPONENTNAME
There are even shorthands for this: the commands generate can be used as g and component as c:
ng g c YOURCOMPONENTNAME
you can use ng --help, ng g --help or ng g c --help for the docs.
Ofcourse rename YOURCOMPONENTNAME to the name you would like to use.
Docs: angular-cli will add reference to components, directives and pipes automatically in the app.module.ts.
Update: This still functions in Angular version 8.