Order of Operations

Migrating a large Angular 1 application to Angular 2 can be a big undertaking.We recommend the following order of operations during conversion.

  • Webpack
  • TypeScript
  • Move as much code as possible into pure TypeScript modules
    • Write framework-agnostic unit tests for that code
    • Good candidates for this are stateless services
  • Enable ngUpgrade
    • If used, replace the ng-app directive with angular.bootstrap.
    • Create UpgradeAdapter singleton and replace "bootstrap".
  • Identify components (directives) of the app most likely to benefit from Angular 2
    • These could be parts of the app where performance is a problem,parts where there will be more active development orparts that could really benefit from Angular 2 libraries or components.
  • Convert all service dependencies from Angular 1 to Angular 2
    • Move existing .factory Angular services to .service
    • Leverage TypeScript classes
    • Use upgradeAdapter.downgradeNg2Provider(ServiceName) to expose Angular 2 service to Angular 1
  • Repeat this process until all components have been converted to Angular 2

原文: https://angular-2-training-book.rangle.io/handout/migrate/ng-upgrade/order_of_operations.html