angular.js - Is the way of introducing third-party libraries different in angular 4 than in angular 2?

Question

I introduced bootstrap according to the angular2 method. No error was reported when I started it, but the style just couldn’t come out. Looking at the console, there was nothing in the <style> tag. The .angular-cli.json configuration is configured.

"styles": [
        "../node_modules/bootstrap/dist/css/bootstrap.css"
      ],

Answer 1

It shouldn’t be that the package has not been downloaded npm i --save bootstrap?