上QQ阅读APP看书，第一时间看更新

Angular app directives

AngularJS allowed declarative bootstrapping the application using the ng-app directive. But, Angular doesn't support declarative bootstrapping. It supports only bootstrapping the application explicitly by calling the bootstrap function and passing the root component of the application.

AngularJS:

<body ng-app="packtPub">

Angular:

import { platformBrowserDynamic } from '@angular/platform-browser-dynamic'; 
import { AppModule } from './app/app.module'; 
platformBrowserDynamic().bootstrapModule(AppModule);

Notice that in AngularJS, the Angular module name packtPub has been assigned to the ng-app directive. However, in Angular, we pass AppModule to the bootstrap module as per the execution environment. Notice that AppModule is the NgModule class, which is the root module of the application that we just bootstrapped as per the execution environment.