Dependency Injection in ASP.NET Core

Building Modular and Testable Applications with Dependency Injection in ASP.NET Core

Introduction:

A key component of developing ASP.NET Core applications that encourages modularity, maintainability, and testability is dependency injection, or DI. In this post, we’ll examine the foundations of dependency injection in ASP.NET Core, as well as its advantages and practical uses for developing organized and expandable applications.

Understanding Dependency Injection:

Dependency injection is a design pattern that assists in the management of dependencies among various components in a software system. It refers to the technique of supplying the objects that a class requires (its dependencies) from outside rather than creating them within the class itself in the context of ASP.NET Core. This method makes classes more modular and testable.

Benefits of Dependency Injection in ASP.NET Core:

1. Modular Code: By injecting dependencies into classes, each class can concentrate on its own functionality without being tethered to the implementation details of its dependencies. As a result, the code becomes more modular and maintainable.

2. Testability: Dependency injection makes unit testing easier by allowing developers to replace real implementations of dependencies with mock or test implementations. This facilitates the isolation and testing of individual components.

3. Extensibility: It is easier to extend an application’s functionality with dependency injection by introducing new components or swapping out existing ones. This is especially useful when evolving and scaling an application.

Implementing Dependency Injection in ASP.NET Core:

1. Service Registration:

Services in ASP.NET Core are registered at application startup in the dependency injection container. Services can be added to the container via the ‘ConfigureServices’ method in the ‘Startup’ class.

public void ConfigureServices(IServiceCollection services)

{

    services.AddTransient<IMyService, MyService>();

    // Add more services...

}

‘IMyService’ is the interface in this example, and ‘MyService’ is the matching implementation. ‘Transient’ means that each time a request is made, a new instance of ‘MyService’ is created.

2. Constructor Injection:

Use the constructor of a class to inject dependencies into it. The necessary dependencies are automatically provided by the DI container when a class instance is created.

public class MyController : Controller

{

    private readonly IMyService _myService;

    public MyController(IMyService myService)

    {

        _myService = myService;

    }

    // Controller actions...

}

3. Using Dependency Injection in Middleware:

Dependency injection can also help middleware components in the ASP.NET Core request processing pipeline. The ‘Invoke’ method can have services injected into it.

public class MyMiddleware

{

    private readonly RequestDelegate _next;

    private readonly IMyService _myService;

    public MyMiddleware(RequestDelegate next, IMyService myService)

    {

        _next = next;

        _myService = myService;

    }

    public async Task Invoke(HttpContext context)

    {

        // Use _myService...

await _next(context);

    }

}

Scopes and Lifetimes of Services:

Several service lifetimes, such as ‘Transient’, ‘Scoped’, and ‘Singleton’, are supported by ASP.NET Core. Managing the lifespan of service instances requires an understanding of these lifetimes.

1. Transient: Whenever an instance is requested, a new one is created.

2. Scoped: Each request generates a single instance. Within the parameters of an HTTP request, it is shared.

3. Singleton: For the duration of the application, only one instance is created.

Best Practices for Dependency Injection in ASP.NET Core:

1. Choose Constructor Injection: For improved readability and maintainability, inject dependencies via the constructor.

2. Employ Interfaces: Write code that checks against interfaces as opposed to specific implementations. This encourages testability and flexibility.

3. Avoid the Service Location Anti-Pattern: Avoid the ‘ServiceLocator’ pattern, which involves retrieving services directly from the container within a class.

4. Register Services as Interfaces: When registering services, use interfaces rather than concrete implementations.

services.AddTransient<IMyService, MyService>();

  Conclusion:

Dependency injection is a powerful design pattern that improves the design, testability, and maintainability of ASP.NET Core applications significantly. Developers can create modular, extensible, and testable applications by leveraging the built-in dependency injection container. Understanding dependency injection principles is critical for developing robust and scalable ASP.NET Core applications.

Learn ASP.NET Online

Introduction to ASP.NET

Microsoft created ASP.NET, which stands for Active Server Pages.NET. Thousands of organizations have utilized Microsoft ASP.NET to construct sophisticated, dynamic websites. It is a strong tool for programmers and developers that work on the development of rich and dynamic web apps and websites. ASP.NET is a Microsoft.NET Framework feature that is not limited to script languages; it may also be used by programmers. Microsoft’s Active Server Page was developed in response to the growing need for dynamic webpages.

It includes a Feature library with various ready-to-use methods and web controls for building applications from the ground up. Microsoft often modifies it to stay current with trends. ASP.NET is well-known for its advantages over alternative online development models, in addition to being a pioneering platform. It benefits both the organizations that use it and the developers who take ASP.NET classes.

In the fast-paced world of software development, knowing the most recent technologies and frameworks is critical. NET is one such technology that has seen enormous progress throughout time. As businesses strive to digitize their processes, the demand for knowledgeable.NET developers has skyrocketed. There are numerous online.NET courses available to meet this need and equip potential developers. The article explores into the area of online.NET courses, underlining their benefits, important components, and potential to boost your career.

Professionals with ASP.NET expertise benefit from things like:

capable to develop applications with ASP.NET.

Thanks to its complementary design and extensive toolkit, the ASP.NET framework provides wonderful features like drag-and-drop server controls and automated deployment, among others.

less time is spent coding and more time is spent creating large online apps.

The combination of HTML and source code makes it easy to construct and maintain websites.

Find lucrative career opportunities as a developer.

Spend less time and effort writing extra code for complex and large-scale applications to save down on development costs.

All students and freshmen interested in using the Microsoft platform to create modern desktop, web, and service-oriented applications are encouraged to take this course.

Pros of Online.NET Courses

The following are advantages for students taking online.NET classes:

Flexibility: With online courses, you may customize your education to fit your schedule and establish your own pace for learning.

Accessibility: No matter where you live in the world, you can access excellent.NET classes.

Interaction: A typical component of online platforms is discussion boards, which allow students to interact with teachers and peers and foster a collaborative learning environment.

Comprehensive Curriculum: Since respectable online courses offer a wide range of.NET topics, you can be confident that you’ll obtain a well-rounded education.

Practical Experience: A lot of courses incorporate practical activities and projects that let you put theory into practice in real-world settings.

All students and freshmen interested in using the Microsoft platform to create modern desktop, web, and service-oriented applications are encouraged to take this course.

To enroll in this course, there are no prerequisites.

Why should I study ASP.NET at Maria Academy (Marz Technologies)?

With more than five years of experience, we have taught ASP.NET online to students all around the world. We have also conducted online training courses in  India and other nations. Our knowledgeable instructors will walk you through the process of creating and launching a dynamic website using the ASP.NET tools.

For beginners and intermediate developers, this course module offers practical experience covering everything from installing and setting up Visual Studio for Web and SQL Server Express to creating web form pages.

You will learn about C# programming, advanced C# ideas, OOPs concepts, database design with SQL Server,.NET and.NET Core, and other subjects.

In addition, you will learn how to establish a live project from Microsoft MVPs and Technical Consultants, as well as how to use Visual Studio 2019 for.NET programming.

We provide a variety of training options, such as corporate training, one-on-one training, and live instruction.

Our Fundamental Course Module:

Introduction to .NET Framework and its Architecture

C# Language Fundamentals

Microsoft SQL Server

Creating ASP.NET Pages

Programming in ASP.NET

ASP.NET MVC training

ENTITY FRAMEWORK

What is Entity Framework?
We (developers) used to frequently write ADO.NET code or Enterprise Data Access Block in Dot NET 3.5 to save or retrieve application data from the underlying database. Microsoft has provided a framework called “Entity Framework” to automate all these database-related activities for your application. Entity Framework is a Microsoft-supported open-source ORM framework for.NET applications. It enables developers to work with data using objects of domain-specific classes without focusing on the underlying database tables and columns where this data is stored.

Entity Framework in C#:
In this article, we will see how to use Entity Framework in C# applications using Visual Studio. The examples in this and likely future articles will use C# under Win Forms, but as previously stated, this choice will not affect a different intended use that the developer may reasonably request.

ORM in C#:
Optical mark recognition (also called optical mark reading or OMR) is the process of using hardware, software, or both to capture fields, for example, marks on documents such as multiple-choice questions, questionnaires with true or false fields, and other document forms.

Types of ORM Fields:

There are numerous types of OMR fields, but this section will give an overview of some of the most common ones. There can be shapes like squares, circles, and ovals.

Why Entity Framework in .NET Applications?
 Entity Framework is an ORM tool, and ORM tools are primarily used to boost developer productivity by eliminating the redundant task of performing CRUD operations against a database in a.NET application.
 Entity Framework can generate the necessary database commands for doing the database CRUD operation, i.e., can generate select, insert, update, and delete commands for us.
 While working with Entity Framework, we can perform different types of operations on the domain objects (basically classes representing database tables) using LINQ to entities.
 Entity Framework will generate and execute the SQL command in the database and then store the results in the instances of your domain objects so that you can do different types of operations on the data.

Prerequisites to Learn Entity Framework:
To fully benefit from this Entity Framework Course, you should have a basic understanding of C# as well as any database such as SQL Server, Oracle, or MySQL. It is recommended that you install the.NET Framework, Visual Studio, and SQL Server on your computer.

Advantages of Entity Framework:
Productivity:
Entity Framework can take up to 35 percent of the entire application code. It makes the developer’s life easier than ever. Despite its limitations, the designer integrated into Visual Studio dramatically simplifies the mapping process.
Maintainability:
Since you have fewer lines of code to fetch data from the database, the fewer lines of code you have to maintain.
Performance:
The complexity of ORM introduces an obvious slowdown in performance. In the entity framework first request to fetch data is a little bit slow but after that is fast to fetch data from the database.
Transactions:
ORM does all possible automation as transactions while querying the data or storing the data periodically. We can also customize transaction management practices to make the most of it out of the entity framework.