Setting environment variables in an AngularJS application happens at the configuration stage; this usually takes place in a separate file containing the configuration data. This is an illustration of how to set environment variables in an AngularJS application:

First Step
To save the environment variables, create a file in the root directory of your application, say config.js.

Step Two
Use the following code to define the environment variables in the file:

"use strict";
 angular.module('config', [])
.constant('ENV', {name:'development',tokenURL:'http://localhost:62511/token',apiURL:'http://localhost:62511/api',biUrl:'http://localhost:4200/',backgroundimage:'../images/backgroundimage.jpg',logo:'images/ogo.png'});

Step 3

Include the config.js file in your HTML file, just like any other JavaScript file:
<script src="scripts/index.config.js"></script>

Step 4

Inject the env constant in your AngularJS controllers, services, or directives to access the environment variables,

angular.module("myApp").controller("MyController", function($scope, env) {
    console.log(env.apiUrl);
    console.log(env.debugEnabled);
});
development: {
        options: {
            dest: '<%= yeoman.app %>/scripts/config.js'
        },
        constants: {
            ENV: {
                name: 'development',
                tokenURL: "http://localhost:62511/token",
                apiURL: "http://localhost:62511/api",
                biUrl: "http://localhost:4200/",
                backgroundimage: "../images/backgroundimage.jpg",
                logo: "images/logo.png",
            }
        }
    },
    qa: {
        options: {
            dest: '<%= yeoman.dist %>/scripts/config.js'
        },
        constants: {
            ENV: {
                name: 'qa',
                tokenURL: "https://qa.hostforlife.eu/token",
                apiURL: "https://qa.hostforlife.eu/api",
                biUrl: "https://qa-dashboard.hostforlife.eut/",
                backgroundimage: "../images/backgroundimage.jpg",
                logo: "images/logo.png",
            }
        }
    },

Grunt command to run the Application,

grunt build --qa

Hashing functions in SQL Server work as cryptographic instruments to produce distinct fixed-size hash values from input data. This compilation features a variety of hash algorithms, all of which are intended to provide unique hash values for a given input string.

• Once-commonly used MD2, MD4, and MD5 algorithms produce hashes with a length of 128 bits. But now since they have flaws, they are considered insecure.
• SHA1 and SHA (Secure Hash Algorithm): These algorithms, which are members of the SHA family, generate hash values with different bit lengths. Even while SHA-1 was once in use, its flaws have made it obsolete in favor of safer substitutes.
• SHA2_256 and SHA2_512: These members of the SHA-2 family provide hash values of 256 and 512 bits, respectively, and are presently regarded as secure in the context of cryptography.

1. Message Digest Algorithm 2, or MD2
A cryptographic hash function called MD2 generates a hash value of 128 bits. Although this older method is renowned for being straightforward, it has flaws and is no longer advised for use in situations where security is a concern.

As an illustration
SELECT HASHBYTES('MD2', 'Hello, World!') AS [MD2 HashValue];

2. MD4 (Message Digest Algorithm 4)
MD4 is a cryptographic hash function designed to produce a 128-bit hash value. It's also considered obsolete and insecure due to vulnerabilities.

Example:
SELECT HASHBYTES('MD4', 'Hello, World!') AS [MD4 HashValue];

3. Message Digest Algorithm 5, or MD5
A popular cryptographic hash algorithm that produces a 128-bit hash result is MD5. However, it is no longer regarded as secure for essential applications because of weaknesses and collision attacks.

As an illustration
SELECT HASHBYTES('MD5', 'Hello, World!') AS [MD5 HashValue];

4. SHA (Secure Hash Algorithm)
The SHA family of cryptographic hash algorithms consists of SHA-1, SHA-2, SHA-3, and SHA-0 (deprecated). More secure versions of SHA-0 and SHA-1 are gradually replacing the deemed weaker ones.

Example
SELECT HASHBYTES('SHA', 'Hello, World!') AS [SHA HashValue];

5. SHA1 (Secure Hash Algorithm 1)
A 160-bit hash value is generated by SHA-1. Although it was widely used, vulnerabilities have caused it to be deprecated. Collision attacks were successful because of its flaws.

Example:

SELECT HASHBYTES('SHA1', 'Hello, World!') AS [SHA1 HashValue];

6. SHA2_256 (Secure Hash Algorithm 2 - 256 bit):
SHA-256 is part of the SHA-2 family and generates a 256-bit hash value. It's currently considered secure and widely used for various cryptographic applications.

Example

SELECT HASHBYTES('SHA2_256', 'Hello, World!') AS [SHA2_256 HashValue];

7. SHA2_512 (Secure Hash Algorithm 2 - 512 bit)
SHA-512, another member of the SHA-2 family, produces a 512-bit hash value. It's a more secure and larger variant of SHA-256.

Example

SELECT HASHBYTES('SHA2_512', 'Hello, World!') AS [SHA2_512 HashValue];

A variety of hash algorithms are available in SQL Server, and each one creates distinct hash values from input strings. Although SHA-1 and MD5 were once widely used, their flaws now warn against using them. As a safe substitute, the SHA-2 family, which includes SHA2_256 and SHA2_512, is used instead.

Selecting an algorithm that strikes a balance between security requirements and performance is crucial. Database professionals can strengthen security protocols and data integrity in SQL Server configurations by understanding these hashing subtleties.

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The concat operator is used in RxJS (Reactive Extensions for JavaScript) to concatenate multiple observables together, sequentially, in the order that they are supplied. It makes ensuring that emissions from observables are processed sequentially and that they are subscribed to.

Set up RxJS
You can use npm to install RxJS if you haven't previously.

npm install rxjs

Import Concat and Any Other Essential Programs
To create observables, import the concat operator along with any additional functions or operators that you require. One way to build observables with values would be to utilize of.

import { concat, of } from 'rxjs';

Basic Syntax of RxJS
import { concat } from 'rxjs';
const resultObservable = concat(observable1, observable2, observable3, ...);

The concat function takes multiple observables as arguments, and it returns a new observable (resultObservable) that represents the concatenation of these observables.

Sequence of Action

• In the order that they are passed to concat, observables are subscribed to.
• Each observable's values are processed one after the other.

Awaiting Finalization

• Concat waits for every observable to finish before proceeding to the following one.
• Subsequent observables won't be subscribed to if an observable never completes, meaning it keeps emitting values forever.

Example
import { concat, of } from 'rxjs';

const observable1 = of(1, 2, 3);
const observable2 = of('A', 'B', 'C');

const resultObservable = concat(observable1, observable2);

resultObservable.subscribe(value => console.log(value));

Output
1 2 3 A B C

In this example, observable1 emits values 1, 2, and 3, and then observable2 emits values 'A', 'B', and 'C'. The concat operator ensures that the values are emitted in the specified order.

Use Cases
concat is useful when you want to ensure a sequential execution of observables.
It's commonly used when dealing with observables that represent asynchronous operations, and you want to perform these operations one after the other.

Error Handling
If any observable in the sequence throws an error, concat will stop processing the sequence, and the error will be propagated to the subscriber.

The concat operator in RxJS is a powerful tool for managing the sequential execution of observables, providing a clear order of operations and waiting for each observable to complete before moving on to the next one.

We will discover how to create a custom autofocus directive in an Angular application in this tutorial.

Required conditions
Basic familiarity with Angular 2 or later; installation of Node and NPM; Visual Studio Code; Bootstrap (Optional)

Make an Angular Project
The command to create an Angular project is as follows.
ng new angapp

Now install Bootstrap by using the following command,
npm install bootstrap --save

Now open the styles.css file and add Bootstrap file reference. To add a reference in the styles.css file add this line.
@import '~bootstrap/dist/css/bootstrap.min.css';

Create  Directive
Create  a new directive using the Angular CLI command
ng generate directive autofocus

Now open autofocus.directive.ts file and add following code
import { Directive, ElementRef, AfterViewInit } from '@angular/core';

@Directive({
  selector: '[Autofocus]'
})
export class AutofocusDirective implements AfterViewInit {
  constructor(private el: ElementRef) {}

  ngAfterViewInit() {
    this.el.nativeElement.focus();
  }
}

Now open app.component.html file and add the following code.
<div class="container" style="margin-top:10px;margin-bottom: 24px;">
  <div class="col-sm-12 btn btn-info">
    Autofocus Directive in Angular Application
  </div>
</div>
<div class="container">
  <input type="text" class="form-control" placeholder="Auto Focused Textbox" Autofocus />
</div>

Now open app.module.ts and following code
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { AutofocusDirective } from './autofocus.directive';


@NgModule({
  declarations: [
    AppComponent, AutofocusDirective
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    FormsModule,
    HttpClientModule
  ],
  providers: [],
  bootstrap: [AppComponent],

})
export class AppModule { }

Now run the application using npm start and check the result.

We discovered how to make a personalized autofocus directive in an Angular application by reading this post.

We will discover how to build a pipe in an Angular application to reverse a string in this tutorial.

Required conditions
Basic familiarity with Angular 2 or later; installation of Node and NPM; Visual Studio Code; Bootstrap (Optional)

The command to create an Angular project is as follows.
ng new angapp

Now install Bootstrap by using the following command.
npm install bootstrap --save

Now open the styles.css file and add the Bootstrap file reference. To add a reference in the styles.css file, add this line.
@import '~bootstrap/dist/css/bootstrap.min.css';

Create a Reverse String Pipe
Now, create a custom pipe by using the following command.
ng generate pipe Reverse

Now open the Reverse.pipe.ts file and add the following code.
import { Pipe, PipeTransform } from '@angular/core';

@Pipe({ name: 'reverseString' })
export class Reverse implements PipeTransform {
  transform(value: string): string {
    if (!value) return value;
    return value.split('').reverse().join('');
  }
}

Now, create a new component by using the following command.
ng g c actionmenu

Now open searchlist.actionmenu.html file and add the following code.
<div class="container" style="margin-top:10px;margin-bottom: 24px;">
    <p>{{ 'Artificial Intelligence' | reverseString }}</p>
</div>

Now open app.component.html file and add the following code.
<div class="container" style="margin-top:10px;margin-bottom: 24px;">
  <div class="col-sm-12 btn btn-info">
    Reverse String Pipe in Angular
  </div>
</div>
<app-actionmenu></app-actionmenu>

Now run the application using npm start and check the result:

Overview
This post will teach us how to recognize an event in an Angular application when a user clicks outside of a component.

Required conditions
Basic familiarity with Visual Studio Code, Angular 2 or higher, Node and NPM installed, and Bootstrap

Make an Angular Project
The command to create an Angular project is as follows.

ng new angapp

Now install Bootstrap by using the following command,
npm install bootstrap --save

Now open the styles.css file and add Bootstrap file reference. To add a reference in the styles.css file add this line.
@import '~bootstrap/dist/css/bootstrap.min.css';

Now create a new component by using the following command,
ng g c actionmenu

Now open actionmenu.component.html file and add the following code.
<div class="sidebar {{show}} panel-group" clickOutside (clickOutside)="works()">
    <div class=" panel panel-default" >
        <div>
            <div class="panel-body">Panel Body</div>
            <div class="panel-footer">Panel Footer</div>
        </div>
    </div>
</div>

Now open actionmenu.component.ts file and add the following code.
import { Component, Input } from '@angular/core';

@Component({
  selector: 'app-actionmenu',
  templateUrl: './actionmenu.component.html',
  styleUrls: ['./actionmenu.component.css']
})
export class ActionmenuComponent {
  @Input() show: boolean=true;

  works() {
    this.show = !this.show;
  }
}

Now open actionmenu.component.css file and add the following code.
.sidebar {
    display: none;
}

.true {
    display: block;
}

.false {
    display: none;
}

Now open app.component.html file and add the following code.
<div class="container" style="margin-top:10px;margin-bottom: 24px;">
  <div class="col-sm-12 btn btn-info">
    How to detect clicks outside in Angular  Application
  </div>
</div>
<div class="container">
  <button type="button" class="btn btn-success" (click)="show = !show">Primary</button>
  <app-actionmenu [show]="show"></app-actionmenu>
</div>

Now open app.component.ts file and add the following code.
import { Component } from '@angular/core';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.css']
})
export class AppComponent {
  title = 'Angular App';
  show:boolean= false;
}

Now create a new directive by using the following command, and the following code in this directive.
ng g directive clickOutside

import { Directive, ElementRef, Input, Output, HostListener, EventEmitter } from '@angular/core';

@Directive({
    selector: '[clickOutside]'
})

export class ClickOutsideDirective {

    constructor(private elementRef: ElementRef) {}

    @Output() clickOutside: EventEmitter<any> = new EventEmitter();

    @HostListener('document: click', ['$event.target']) onMouseEnter(targetElement:any) {
        const clickInside = this.elementRef.nativeElement.contains(targetElement);
        if (!clickInside) {
            this.clickOutside.emit(null);
        }
    }
}

Now open app.module.ts and following code.
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';
import { FormsModule } from '@angular/forms';
import { HttpClientModule } from '@angular/common/http';
import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { ActionmenuComponent } from './actionmenu/actionmenu.component';
import { ClickOutsideDirective } from './click-outside.directive';
@NgModule({
  declarations: [
    AppComponent,
    ActionmenuComponent,ClickOutsideDirective
  ],
  imports: [
    BrowserModule,
    AppRoutingModule,
    FormsModule,
    HttpClientModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Now run the application using npm start and check the result.

Click outside anyplace in the component after clicking the button. This tutorial taught us how to detect events in the Compoent Angular application when a user clicks outside of any location.

A software design pattern called CQRS (Command Query Responsibility Segregation) divides up who is responsible for accessing and writing data in a system. The same set of components are frequently used in traditional design patterns for both reading and writing data. CQRS introduces two distinct models to suggest the division of these duties.

• Command Model: The command model handles event triggering, data store updating, and command processing and validation.
• Query Model: This model manages the processes involved in getting data out of the system.

The four major concepts of CQRS are listed below:

• Command: Action or request to modify the system's status
• Query: An occurrence or a request to obtain data from the system
• Command Handler: An element in charge of processing commands and adjusting the system's state.
• Query Handler: An element in charge of managing queries and getting information out of the system.

CQRS Offers Advantages like:

• Scalability: Because the application supports several read and write data models, it can be scaled.
• Flexibility: It permits the use of distinct data stores that are best suited for writing and reading processes.
• Performance: There is room for improvement with this application.

This CQRS Model may be used with Nest JS; in this tutorial, we'll discover how to do it.

We'll use the creation and retrieval of a TODO application as an example using the CQRS paradigm.

Application for TODOs using CQRS pattern
You must use the command line to install nest cli if it is not already installed globally on your computer.
npm i -g @nestjs/cli

Create new Nest Js project if not created already using below command
nest new todo-application

Dependency Installation
Nest JS provides a package to implement CQRS, we need to install the package first using below command
npm install --save @nestjs/cqrs

Module Creation
Create new Module for our TODO application using command
nest generate module todo

Commands
Commands are used to change the application state, when a command is triggered, it is handled by corresponding command handler. Then handler will be responsible to process the operation. Every command will have command handler in order to process the command

Create new file inside todo module with name create-todo-command.ts and implement the below code
import { ICommand } from '@nestjs/cqrs';

export class CreateToDoCommand implements ICommand {
    constructor(
      public readonly title: string,
      public readonly description: string,
    ) {}
}

Command Handler
Create new file inside todo module with name create-todo-command-handler.ts  and implement the below code

import { CommandHandler, ICommandHandler } from '@nestjs/cqrs';
import { CreateToDoCommand } from './create-todo-command';

@CommandHandler(CreateToDoCommand)
export class CreateToDoHandler implements ICommandHandler<CreateToDoCommand> {
  async execute(command: CreateToDoCommand): Promise<void> {
    // Add Logic to do validation and business rule
    const { title, description } = command;

    // Use Repository to save directly or Create Factory to add business logic and save
  }
}

Query
Queries are used to retrieve the data from the application, when a query is requested, Query handler handles the requests and retrieves the data. Every query will have query handler

Create new file inside todo module with name get-todo-query.ts  and implement the below code
import {  IQuery } from '@nestjs/cqrs';

export class GetToDoQuery implements IQuery {
    constructor() {}
}

Query Handler
Create new file inside todo module with name get-todo-query-handler.ts  and implement the below code
import { IQueryHandler, QueryHandler } from '@nestjs/cqrs';
import { GetToDoQuery } from './get-todo-query';

@QueryHandler(GetToDoQuery)
export class GetToDoQueryHandler implements IQueryHandler<GetToDoQuery> {
  async execute(query: GetToDoQuery): Promise<any> {
    // Fetch data using repository or factory and return it
    // Sample Response
    return [
      { id: 1, title: 'Test', description: 'Reminder to complete daily activity' },
      { id: 2, title: 'Test 2', description: 'Reminder to complete daily activity2' },
    ];
  }
}

Module
In the todo.module.ts  file, import the CQRS module to use the command handlers and query handlers
import { Module } from '@nestjs/common';
import { CqrsModule } from '@nestjs/cqrs';
import { ToDoController } from './todo.controller';
import { CreateToDoHandler } from './create-todo-command-handler';
import { GetToDoQueryHandler } from './get-todo-query-handler';

@Module({
  imports: [CqrsModule],
  controllers: [ToDoController],
  providers: [CreateToDoHandler, GetToDoQueryHandler],
})
export class ToDoModule {}

Controller
Create todo.controller.ts  file to handle the API request and use command and query bus
import { Controller, Get, Post, Body } from '@nestjs/common';
import { CommandBus, QueryBus } from '@nestjs/cqrs';
import { CreateToDoCommand } from './create-todo-command';
import { GetToDoQuery } from './get-todo-query';

@Controller('ToDo')
export class ToDoController {
  constructor(
    private readonly commandBus: CommandBus,
    private readonly queryBus: QueryBus,
  ) {}

  @Post()
  async createToDo(@Body() body: { title: string, description: string }): Promise<void> {
    const { title, description } = body;
    await this.commandBus.execute(new CreateToDoCommand(title, description));
  }

  @Get()
  async getToDo(): Promise<any[]> {
    return this.queryBus.execute(new GetToDoQuery());
  }
}

Pro Tips
You can create a separate folder for command and query to segregate the code and make it more readable. Also, here I just gave the basic high level demo, but in your application, you can create dto for command and query, and you can directly use that dto
Conclusion

In conclusion, while CQRS can provide advantages in terms of scalability and flexibility, it comes with increased complexity and potential challenges in terms of consistency and development overhead. It is important to carefully consider whether the benefits align with the specific requirements and goals of the application being developed.

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In the ever-changing world of web development, selecting a front-end framework is analogous to deciding on a skyscraper's foundation. It must be tough, adaptable, and well-suited to the job at hand. Understanding the subtleties of multiple frameworks is critical for creating seamless and responsive user interfaces as developers. This essay delves into the complexities of various prominent frontend frameworks, including React.js, Angular, Vue.js, Svelte, and Ember.js, revealing their distinct capabilities and optimal use cases.

React.js
React.js, a Facebook product, is at the forefront of frontend development. Its claim to fame is its component-based architecture, which allows for the creation of modular and reusable user interfaces. The virtual DOM in React assures optimal rendering speed, making it an excellent choice for single-page applications (SPAs) and scenarios requiring real-time changes.

Case Studies

• React's ability to swiftly update and render components makes it a standout performer for SPAs, giving users with a seamless and dynamic experience.
• Component-Based Architecture: React.js is extremely useful for developers who want a modular and scalable development strategy. Code reuse and maintainability are aided by the ability to design self-contained components.
• Real-Time Applications: From live conversations to collaborative editing, React's virtual DOM shines in applications requiring rapid updates and real-time interactions.

Angular
Angular is a full-fledged framework developed by Google that is meant for sturdy and feature-rich apps. Its Model-View-Controller (MVC) architecture offers a structured framework for large-scale projects. The robust capabilities in Angular's armory, including as two-way data binding and dependency injection, make it a force to be reckoned with in enterprise-level applications.

Use Cases

• Enterprise-level Applications: Angular's comprehensive feature set and MVC architecture make it a powerhouse for building large-scale applications with complex requirements.
• Progressive Web Apps (PWAs): With built-in service workers and a focus on performance, Angular is a go-to choice for crafting high-quality PWAs that deliver a native app-like experience.
• Data-Intensive Applications: Projects requiring heavy data manipulation benefit from Angular's two-way data binding, simplifying the process of managing and updating data.

Vue.js
Vue.js is a frontend framework that stands out for its simplicity and versatility. Vue.js, created by Evan You, has a progressive approach, allowing developers to smoothly integrate it into projects of varied sizes. Because of its lightweight nature and adaptability, it is an ideal solution for small to medium-sized projects, as well as scenarios requiring rapid prototyping.

Use Cases
Small to Medium-sized Projects: Vue.js's lightweight nature and easy learning curve make it an excellent fit for projects where simplicity and efficiency are paramount.
Prototyping: Rapid prototyping becomes a breeze with Vue.js, as its simplicity allows developers to iterate quickly over designs and concepts.
Highly Customizable Projects: Vue.js offers a high degree of customization, making it suitable for projects that demand tailored solutions and adaptability.

Svelte
Svelte, a relative newcomer to the frontend scene, takes a different approach by shifting the heavy lifting from the browser to the build step. It compiles components into highly optimized JavaScript at build time, resulting in smaller and faster applications.

Use Cases

• Performance-Critical Applications: Svelte's compilation approach results in highly optimized code, making it suitable for applications where performance is a top priority.
• Developer Experience: With a syntax that closely resembles standard HTML and JavaScript, Svelte offers a refreshing developer experience, reducing boilerplate code and enhancing readability.
• Small to Medium-sized Projects: Svelte's compilation model makes it an efficient choice for smaller projects where rapid development is crucial.

Ember.js

Ember.js, an opinionated framework, comes with conventions that guide developers through the entire application development lifecycle. It focuses on productivity and developer happiness by providing a set structure and conventions for building ambitious web applications.

Use Casesarge-Scale Applications: Ember.js shines in projects requiring a high level of organization and structure, making it an excellent choice for large-scale applications.

• Opinionated Development: Teams that prefer clear conventions and predefined structures benefit from Ember.js's opinionated approach, reducing decision fatigue and promoting consistency.
• Long-term Maintenance: The conventions and structure of Ember.js contribute to long-term maintainability, making it suitable for projects with extended lifecycles.

Conclusion

In the dynamic landscape of frontend development, the choice between React.js, Angular, Vue.js, Svelte, and Ember.js is a nuanced decision influenced by the specific needs of each project. React.js excels in SPAs and real-time applications, Angular proves its mettle in enterprise-level and data-intensive projects, Vue.js provides a lightweight and flexible solution for smaller projects and rapid prototyping, Svelte offers optimized performance with a unique compilation approach, and Ember.js provides a structured, opinionated framework for large-scale applications. By carefully considering the unique features and strengths of each framework, developers can make informed decisions that align with project requirements, ensuring the successful creation of web applications that stand the test of time.

The Repository Pattern is a popular design pattern for separating data access and manipulation logic from the rest of the application. While the Repository Pattern is more frequently linked with backend or server-side development, you can still use a variant of it in Angular for data management. Here's an example of how to use Angular to construct a simplified version of the Repository Pattern:

Make a Repository
To handle data operations, create a repository. Create a file called user.repository.ts with the following code:

import { Injectable } from  ‘@angular/core’;
import { HttpClient } from ‘@angular/common/http’;
import { Observable } from ‘rxjs’;
import { User } from ‘./user.model’;
@Injectable({
providedIn: ’ root ’ ,
})
 export class UserRepository {
private apiUrl = ‘https://api.example.com/users’;
constructor(private http: HttpClient) {}
getAllUsers(): Observable<User[]>{
                return this.http.get<User[]>(this.apiUrl);
}
getUserById(id:number): Observable<User>{
                return this.http.get<User>(‘${this.apiUrl}/${id}’);
}
createUser(user:User): Observable<User>{
                return this.http.post<User>(this.apiUrl,user);
}
updateUser(user:User): Observable<User>{
                return this.http.put<User>(>(‘${this.apiUrl}/${user.id}’, user);
}
deleteUser(id:number): Observable<any>{
                return this.http.delete(>(‘${this.apiUrl}/${id}’);
}
}

Use the Repository in a Component
Make a component that makes use of the repository for data operations. Create a file called user.component.ts with the following code:

import { Component,OnInit } from ‘@angular/core’;
import { User } from ‘./user.model’;
import { UserRepository } from ‘./user.repository’;
@Component({
     selector: ‘app-user’,
     template:’
       <h2>User Component</h2>
        <ul>
             <li *ngFor=”let user of users”>{{ user.name}}</li>
        </ul>
})
export class UserComponent implements OnInit {
    users:User[];
    constructor( private userRepository: UserRepository) {}
    ngOnInit(): void {
       this.loadUsers();
    }
    loadUsers():void{
     this.userRepository.getAllUsers().subscribe((users:User[]) => {
            this.users = users;
     });
    }
}

Activate the Repository
Import the UserRepository into the app.module.ts file. Include it in the providers array of the @NgModule decorator. As an example:

import { NgModule } from ‘@angular/core’;
import { BrowserModule } from ‘@angular/platform-browser’;
import { HttpClientModule } from ‘@angular/common/http’;
import { UserRepository } from ‘./user.repository’;
import { UserComponent } from ‘./user.component’;
@NgModule({
       declarations: [UserComponent],
       imports : [BrowserModule,HttpClientModule],
       providers : [UserRepository],
       bootstrap : [UserComponent],
})
export class AppModule {}

Create and launch the program
To build and serve the Angular application, use the following command:

ng provide

Your app will be available at http://localhost:4200.

The UserRepository in this example encapsulates the data operations for managing users. The repository is used by the UserComponent by injecting it into its constructor and using its methods to retrieve user data.

You separate the code for data access and manipulation from the components by using this simplified version of the Repository Pattern in Angular. This encourages code reuse, testability, and maintainability while also providing a clear interface for working with the data layer.

What exactly is Angular routing?
Angular routing is a useful feature that allows you to create single-page applications (SPAs) by allowing navigating between different views or components within your Angular application without having to reload the entire page. Angular routing, as opposed to traditional server-side navigation, which results in a new HTTP request and a whole new page for each link or action, provides a seamless and dynamic user experience within the same page. Routing is extremely important in online development, especially in the context of single-page applications (SPAs) and current web frameworks.

Navigation in a Single-Page Application (SPA)
The program runs within a single HTML page with SPAs, and routing allows users to navigate between different views or areas of the application without having to reload the entire page. This leads in a more fluid and responsive user experience.

Loading of Dynamic Content
By allowing components or views to be loaded asynchronously as needed, routing enables dynamic content loading. This is especially significant for large applications with a high number of components because it aids in improving the first page load time.
enhanced user experience

Routing adds to a more pleasant and seamless user experience. Users can move between portions of the application with smooth transitions, giving the application the appearance of a regular desktop application.

Structure of Modular Application
Routing encourages the application to have a modular structure. Each route can be linked to a different component or feature, resulting in a better ordered and maintainable codebase. Let's start with a basic blog project to learn about routing in Angular.

Step 1. Create a New Angular Project
ng new my-blog

Follow the prompts to set up your project. You can choose options like stylesheets format (CSS, SCSS, etc.) and whether you want Angular routing or not.

Step 2. Navigate to the Project Directory
cd my-blog

For Example path. D:\CSharpCorner\Project\Angular which contain Project my-blog  we need to navigate into the Folder by using cd command in Terminal.
cd D:\CSharpCorner\Project\Angular\my-blog.

Step 3.  Create Components
ng generate component home
ng generate component about
ng generate component Services
ng generate component Blog

Step 4. Set Up Routes
Open the src/app/app-routing.module.ts file, which Angular CLI generates if you choose routing during project creation. Configure your routes in this file.
import { NgModule } from '@angular/core';
import { RouterModule, Routes } from '@angular/router';

import { HomeComponent } from './home/home.component';
import { AboutComponent } from './about/about.component';
import { ServicesComponent } from './services/services.component';
import { BlogComponent } from './blog/blog.component';

const routes: Routes = [
  { path: '', component: HomeComponent },
  { path: 'about', component: AboutComponent },
  { path: 'services', component: ServicesComponent },
  { path: 'blog', component: BlogComponent },
];
@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { }

Step 5. Update App Module
Open src/app/app.module.ts and make sure to import and include the AppRoutingModule.
import { NgModule } from '@angular/core';
import { BrowserModule } from '@angular/platform-browser';

import { AppRoutingModule } from './app-routing.module';
import { AppComponent } from './app.component';
import { HomeComponent } from './home/home.component';
import { AboutComponent } from './about/about.component';
import { ServicesComponent } from './services/services.component';
import { BlogComponent } from './blog/blog.component';

@NgModule({
  declarations: [
    AppComponent,
    HomeComponent,
    AboutComponent,
    ServicesComponent,
    BlogComponent
  ],
  imports: [
    BrowserModule,
    AppRoutingModule
  ],
  providers: [],
  bootstrap: [AppComponent]
})
export class AppModule { }

Step 6. Update App Component HTML
Update src/app/app.component.html to include the <router-outlet> directive.
<!-- app.component.html -->

<header>
  <nav>
    <ul>
      <li><a routerLink="/" routerLinkActive="active">Home</a></li>
      <li><a routerLink="/about" routerLinkActive="active">About</a></li>
      <li><a routerLink="/services" routerLinkActive="active">Services</a></li>
      <li><a routerLink="/blog" routerLinkActive="active">Blog</a></li>
    </ul>
  </nav>
</header>

<main>
  <!-- Your router-outlet or other content goes here -->
  <router-outlet></router-outlet>
</main>

JavaScript

Step 7. Update App Component CSS

Update src/app/app.component.css file.

/* styles.scss */

/* Reset some default margin and padding for the page */
body, h1, h2, h3, p {
  margin: 0;
  padding: 0;
}

/* Apply a basic style to the header */
header {
  background-color: #333;
  color: white;
  padding: 10px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

/* Style the logo */
.logo img {
  height: 40px; /* Adjust the height as needed */
}

/* Style the navigation menu */
nav ul {
  list-style: none;
  display: flex;
}

nav ul li {
  margin-right: 20px;
}

nav ul li a {
  text-decoration: none;
  color: white;
  font-weight: bold;
  font-size: 16px;
  transition: color 0.3s ease-in-out;
}

nav ul li a:hover {
  color: #ffcc00; /* Change to your desired hover color */
}

/* Apply some spacing for the main content */
main {
  padding: 20px;
}

Step 8. Serve the Application
Run the application using the following command.
ng serve -o

You should see your basic Angular app with routing in action.

Step 9. Test Navigation
Click on the "Home" and "About" links to see the content of the corresponding components being displayed without full page reloads.

Summary
Angular routing enhances user experience in SPAs by enabling seamless navigation.Routing allows for dynamic content loading, optimizing performance.A modular application structure is encouraged through the association of routes with specific components.

The provided steps demonstrate the creation of a simple blog project with Angular routing.

If you encounter any issues or have further questions, feel free to let me know, and I'll be glad to assist.

Thank you for reading, and I hope this post has helped provide you with a better understanding of  Routing in Angular.

"Keep coding, keep innovating, and keep pushing the boundaries of what's possible.

Happy Coding.