Angular is a powerful front-end framework for building dynamic web applications. Whether you're a seasoned Angular developer or just getting started, having a handy cheat sheet can be a valuable resource for speeding up development and solving common tasks. In this Angular cheat sheet, we'll cover key concepts, directives, and tips to help you work efficiently with Angular.

Getting Started with Angular

Creating a New Angular Project

ng new my-app

Starting the Development Server

ng serve

Generating a New Component

ng generate component my-component

Angular Basics

Interpolation (Binding Values)

{{ variableName }}

Property Binding

[src]="imageUrl"

Event Binding

(click)="methodName()"

Two-Way Data Binding

[(ngModel)]="propertyName"

Structural Directives

*ngIf

<div *ngIf="showElement">Visible when showElement is true</div>

*ngFor

<div *ngFor="let item of items">{{ item }}</div>

*ngSwitch

<div [ngSwitch]="value">
  <div *ngSwitchCase="'case1'">Content for case 1</div>
  <div *ngSwitchCase="'case2'">Content for case 2</div>
  <div *ngSwitchDefault>Default content</div>
</div>

Component Interaction

Input Binding

<app-child [inputProperty]="parentProperty"></app-child>

Output Binding

<app-child (outputEvent)="parentMethod($event)"></app-child>

Forms

Template-Driven Forms

<form #form="ngForm" (ngSubmit)="submitForm(form)">
  <input type="text" name="name" ngModel>
  <button type="submit">Submit</button>
</form>

Reactive Forms

<form [formGroup]="formGroup" (ngSubmit)="submitForm()">
  <input type="text" formControlName="name">
  <button type="submit">Submit</button>
</form>

HTTP Requests

Import HttpClientModule

import { HttpClientModule } from '@angular/common/http';

Making a GET Request

import { HttpClient } from '@angular/common/http';

constructor(private http: HttpClient) {}

this.http.get('https://api.example.com/data').subscribe(data => {
  console.log(data);
});

Routing

Configuring Routes

const routes: Routes = [
  { path: 'home', component: HomeComponent },
  { path: 'about', component: AboutComponent },
  { path: '', redirectTo: '/home', pathMatch: 'full' },
];

Router Outlet

<router-outlet></router-outlet>

Services

Creating a Service

ng generate service my-service

Injecting a Service

constructor(private myService: MyService) {}

Lifecycle Hooks

ngOnInit

ngOnInit() {
  // Initialization logic here
}

ngOnChanges

ngOnChanges(changes: SimpleChanges) {
  // Handle changes here
}

Tips and Tricks

• Use the Angular CLI for code generation and project setup.
• Leverage Angular CLI's powerful commands like ng generate component and ng generate service.
• Utilize Angular's dependency injection system for managing services.
• Follow best practices for component and module organization.
• Take advantage of Angular's built-in directives for data binding and DOM manipulation.
• Regularly check Angular's official documentation and community resources for updates and solutions to common issues.

This Angular cheat sheet provides a quick reference guide to some of the most commonly used features and concepts in Angular development. Keep it handy as you work on your Angular projects, and don't hesitate to explore the official Angular documentation and community resources for more in-depth information and tutorials. Happy coding!