What are the application scenarios of angularjs? Introduction to application scenarios of angularjs

This article mainly tells you about the application scenarios of angularjs, as well as the application of angularjs. There is not much content. I hope everyone can read it carefully. Let us read this article together.

First of all, let’s talk about the application scenarios of angularjs:

The working principle of AngularJS is: the HTML template will be parsed into the DOM by the browser, and the DOM structure becomes Input to the AngularJS compiler. AngularJS will traverse the DOM template to generate corresponding NG instructions. All instructions are responsible for setting data binding for the view (that is, ng-model in HTML). Therefore, the NG framework only starts to work after the DOM is loaded. It is tried on large browsers and large website projects.

Now let’s talk about the application scenarios of angularjs:

Angular is a popular enterprise-level framework that many programmers use to build and maintain complex Web application. Angular has huge popularity and is used by as many companies as Domino’s Pizza: Ryanair, iTunes Connect, PayPal Checkout, Google. Angular is an open source framework powered by Google. Angular calls itself an extension to HTML for building complex web applications. If you are also familiar with TypeScript, you can take a look at how to write Angular 2.

Angular adopts the MVC architecture. It provides double data binding between the Model layer and the View layer. The advantage of this data binding method is that no matter which side of the data changes, the data on both sides will be automatically updated. This helps you build consumable View components. It also provides a service framework for easy interaction between front-end and back-end services. Best of all, it's simple JavaScript.

When to use AngularJS? When you build a complex web front-end application and need a single module framework to handle everything.

Introduction to angularjs application:

angular application: Use HTML with angular extended syntax to write templates, use component classes to manage these templates, and use services to add application logic. Components and services are packaged and published in modules. Start the application by booting the root module. Angular takes over and displays the application content in the browser, and responds to user interactions according to the operation instructions we provide.

These terms are very important and run through Angular application development. (If you want to know more about angularjs, go to the PHP Chinese website AngularJS Reference Manual column)

The 8 main building blocks of angular applications:

• modulesmodules

• components

• templatetemplate

• Metadatametadata

• Data bindingdata binding

• Directive

• Services services

• Dependency injection

angular module:

angular application is modular , has its own module system called angular module/NgModules.

What exactly is a module? What does modularity mean in angular?

An angular application has at least one module (root module) called AppModule.

Most applications have many other feature modules, which are formed by a set of domain classes, workflows, or closely related functional aggregations.

All modules in angular are classes with the @NgModule decorator.

angular’s ​​module is a class! ! !

Decorators are functions used to decorate JavaScript classes. Responsible for attaching metadata to classes.

• #NgModule is a decorator function that receives a metadata object describing module properties. The attributes are:

• declarations: View classes owned by this module. Angular has three view classes: components, directives, and pipelines.

• exports: A subset of declarations that can be used for component templates in other modules.

• imports: Classes in the component template of this module that need to be exported by other templates.

• providers: The creator of the service. This module adds them to the global service table so that they can be accessed from any part of the application.

• bootstrap: Identifies the main view (root component) of the application. Only the root module can set this property.

Here is a simple root module:

// app.module.ts
import { NgModule }   from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
// @NgModle 装饰器函数，接受一个对象，对象有几个属性
@NgModule({
 imports:   [ BrowserModule ],
 providers:  [ Logger ],
 declarations: [ AppComponent ],
 exports:   [ AppComponent ],
 bootstrap:  [ AppComponent ]
})
// AppComponent 的 export 语句导出，根模块不需要导出，其他组件不需导入根模块。
export class AppModule { }

Boot the root module to start the application. Guide the AppModule in the main.ts file:

// app/main.ts
import { platformBrowserDynamic } from '@angular/platform-browser-dynamic';
// 从app.module 文件导入了 AppModule
import { AppModule } from './app.module';
platformBrowserDynamic().bootstrapModule(AppModule);

At this time, the project only has the app/app.module.ts file and app/main.ts. The former defines the root module of the application, and the latter refers to it to start. application.

Okay, that’s the article introducing the application scenarios and applications of angularjs (if you want to learn more about angularjs, I recommend you to the PHP Chinese website AngularJS Learning Manual column Study), if you have any questions, you can leave a message below.

【Editor’s Recommendation】

What are the differences between angularjs and Vue? Comparison details between angularjs and Vue

What are the advantages of angularjs? Here are the seven advantages of angularjs that you must know

The above is the detailed content of What are the application scenarios of angularjs? Introduction to application scenarios of angularjs. For more information, please follow other related articles on the PHP Chinese website!