System Requirements for installing Angular:
- Node.js - Active LTS or Maintenance LTS
- NPM or Yarn
Install Angular CLI globally using Yarn (or NPM):
yarn global add @angular/cli.
Angular CLI is used to create project, generate application and
library code. It also includes a server for running app locally.
Initialize Angular Application⚑
Angular Applications are generated with Angular CLI. The CLI app makes it easier
to bootstrap any project. Here's how to generate boilerplate code for a new
ng new APP_NAME.
Running the Application⚑
To run an application, simply navigate to the project directory and run
ng serve --open. That's it.
Angular is a platform and MVC framework for building client-side application using HTML and TypeScript.
The basic building blocks for an app is Component known as ngModule. These ngModules collectivelly define an Angular App. An App always has at least a root module that enables bootstrapping.
- defines View. A View is a set of screen elements
- uses Services. A Service provides specific functionality not directly related to views
- Service Providers can be injected into components as dependencies, making the codebase modular, reusable and efficient.
An NgModule is made-up of Views and Services
- ngModule declares a compilation context
- ngModule associate its components with related code to form a functional units
- an ngModule can import and export other ngModules
Modularity helps in keeping code clean and maintainable. It also allows developers to take advantages of framework-specific features such as Lazy Loading.
- has at least one component, know as the root component
- defines a class that contains application data and logic, and associated with an HTML
Template, Directives and Data Binding⚑
Angular supports two-way data binding
Templates combine HTML with Angular markup that can modify HTML elements before they are displayed.
- Template Directives provide program logic
- Binding markup connects application data and the DOM
Angular evaulates the directives and resolves binding syntax in the template to modify HTML elements and DOM. Angular does it before the view is displayed in the browser.
Services and Dependency Injection⚑
A class can be made available as a
Service by calling
decorator and immediately writing the class.
@Injectable decorator provides metadata that allows other providers to be
injected as dependency.
A service class is not associated with any specific View, rather they are share by multiple views and injected as a dependency whenever necessary.