Contrasting the Characteristics of ASP.NET Core and ASP.NET Framework

Published in

Simform Engineering

10 min readSep 5, 2023

Brief discussion on ASP.NET core vs ASP.NET framework.

ASP.NET Core and ASP.NET Framework are both popular frameworks for building web applications using Microsoft technologies. While they share some similarities, they have distinct differences that can influence your development choices. In this blog, we will compare ASP.NET Core and ASP.NET Framework, discussing their key features, performance, and some examples to help you understand for your web development projects.

To put it simply, the ASP.NET Framework is like a sturdy foundation for Windows-based applications, while ASP.NET Core is a flexible and portable platform that enables developers to create applications that can run on multiple operating systems.

What is ASP.NET Core?

ASP.NET Core is an open-source, cross-platform, and modular framework developed by Microsoft for building modern, scalable, and high-performance applications. It is the successor to ASP.NET Framework and was first released in 2016. ASP.NET Core is designed to address the limitations of the traditional ASP.NET Framework and cater to the evolving needs of software development in the modern era.

What is ASP.NET Framework?

ASP.NET Framework has been the primary platform for developing Windows applications for many years. It is a comprehensive and mature framework that provides a vast array of libraries, APIs, and runtime environments for building Windows desktop applications, web applications, and web services. The framework is compatible with various programming languages, including C#, VB, ASP.NET, and F#.

Comparing and Understanding the Key Concepts

Let’s take a quick comparative look at both technologies on key aspects like architecture, dependency injection, middleware, and more.

1. Architecture and Compatibility

ASP.NET Core:

.NET Core was designed with modularity and cross-platform compatibility in mind, utilizing the Core CLR (Common Language Runtime). The platform boasts an open-source nature, granting developers the flexibility to optimize the framework’s composition by selecting only the necessary components. This results in the creation of leaner, more efficient deployment packages.
Since .NET Core was developed as a cross-platform successor to .NET Framework, there are some differences in terms of compatibility. While .NET Core provides a subset of APIs from .NET Framework, it supports the .NET Standard specification, ensuring compatibility with libraries and code targeting .NET Standard.

ASP.NET Framework:

The .NET Framework, designed primarily for Windows, adopts a monolithic architecture encompassing the Common Language Runtime (CLR) and an extensive collection of libraries and APIs. It heavily depends on Windows-exclusive functionalities and lacks native support for non-Windows platforms.
Centered around Windows, the .NET Framework thrives on all compatible Windows editions. Consequently, applications developed for the .NET Framework may necessitate adjustments to operate on the .NET Core environment.

2. Dependency Injection

ASP.NET Core: Comes with built-in support for dependency injection, promoting a loosely coupled architecture and making it easier to manage dependencies within your application.

Implementation: logging messages to a file

Step 1: Create a new ASP.NET Core project using the command-line interface (CLI):

logging messages to a file

dotnet new web -n LoggingToFileExample

Step 2: Define the interface for the logging service:

// ILoggerService.cs 
public interface 
ILoggerService 
{ 
    void Log(string message); 
}

Step 3: Implement the logging service:

// FileLoggerService.cs 
public class FileLoggerService : ILoggerService 
{ 
  public void Log(string message) 
  { 
      // Logic to write the log message to a file           
      File.AppendAllText("log.txt", $"{DateTime.Now}: {message}\n"); 
  } 
}

Step 4: Register the logging service in the Startup.cs file:

// Startup.cs 
public void ConfigureServices(IServiceCollection services) 
{ 
    services.AddControllersWithViews(); 
    services.AddScoped<ILoggerService, FileLoggerService>(); 
}

Step 5: Use the logging service in a controller:

// HomeController.cs 
public class HomeController : Controller 
{ 
  private readonly ILoggerService _logger; 
  public HomeController(ILoggerService logger) 
  { 
      _logger = logger; 
  } 
  public IActionResult Index() 
  { 
      _logger.Log("Home page accessed."); 
      return View(); 
  } 
}

However, in .NET Core, there’s a built-in DI container that provides basic dependency injection capabilities, and constructor injection is the default method.

ASP.NET Framework: Although ASP.NET Framework is robust and reliable, it can be less performant, especially in high-load scenarios. It requires a full ASP.NET Framework installation, which may affect application performance.

Implementation: logging messages to a file

Step 1: Create a new ASP.NET Framework project in Visual Studio.

Step 2: Define the interface for the logging service:

// ILoggerService.cs 
public interface ILoggerService 
{ 
    void Log(string message); 
}

Step 3: Implement the logging service:

// FileLoggerService.cs 
public class FileLoggerService : ILoggerService 
{ 
  public void Log(string message) 
  { 
      // Logic to write the log message to a file 
      File.AppendAllText("log.txt", $"{DateTime.Now}: {message}\n"); 
  } 
}

Step 4: Register the logging service in the Global.asax.cs file:

protected void Application_Start() 
{ 
    AreaRegistration.RegisterAllAreas();  
    RouteConfig.RegisterRoutes(RouteTable.Routes);  
    DependencyResolver.SetResolver(new MyDependencyResolver()); 
}

Step 5: Implement a custom dependency resolver:

// MyDependencyResolver.cs 
public class MyDependencyResolver : IDependencyResolver 
{ 
  private readonly ILoggerService _loggerService; 
  public MyDependencyResolver() 
  { 
      _loggerService = new FileLoggerService(); 
  } 
  public object GetService(Type serviceType) 
  { 
      if (serviceType == typeof(ILoggerService)) 
      {  
          return _loggerService; 
      } 
      return null; 
  } 
  public IEnumerable<object> GetServices(Type serviceType) 
  { 
      return new List<object>(); 
  } 
}

Step 6: Use the logging service in a controller:

// HomeController.cs 
public class HomeController : Controller 
{ 
  private readonly ILoggerService _logger; 
  public HomeController() 
  { 
       _Logger=(ILoggerService)DependencyResolver.Current.GetService(typeof(ILoggerService)); 
  } 
  public ActionResult Index() 
  { 
       _logger.Log("Home page accessed."); 
       return View(); 
  } 
}

In .NET Framework, developers often use third-party DI containers, giving them more customization options, but it lacks a standardized built-in container. The fundamental principles of Dependency Injection apply to both frameworks, but the implementation details can vary.

3. Middleware

It allows developers to insert custom code into the request processing pipeline, enabling various functionalities such as authentication, logging, error handling, caching, and more.

A middleware of a component in a spirited core has access to both the incoming requests and the outgoing response, so in a merger, a component may process an incoming request and then pass that request to the next piece of middleware in the pipeline for further processing.

ASP.NET Core: ASP.NET Core offers a more straightforward and modern syntax with built-in support. It has simpler syntax and uses more modern constructs like Task and async/await, making it more in line with modern C# practices.

Implementation: Error Handling Middleware

// ErrorHandlingMiddleware.cs 
public class ErrorHandlingMiddleware 
{ 
  private readonly RequestDelegate _next; 
  public ErrorHandlingMiddleware(RequestDelegate next) 
  { 
      _next = next; 
  } 
  public async Task Invoke (HttpContext context) 
  { 
    try 
    { 
        await _next(context); 
    } 
    catch (Exception ex) 
    { 
        // Log the exception 
        LogException(ex); 
        // Return an appropriate error response to the client
        context.Response.Clear(); context.Response.StatusCode = 500; 
        // Internal Server Error 
        await context.Response.WriteAsync("An error occurred while processing your request."); 
    } 
  } 
  private void LogException(Exception ex) 
  { 
      // Custom logging logic to log the exception 
  } 
}

Explanation: In ASP.NET Core, the Error Handling Middleware is a simple class with a constructor that takes a RequestDelegate. The RequestDelegate represents the next middleware in the pipeline. Inside the Invoke method, the middleware calls the Next middleware using await _next(context);. If any exception occurs during the execution of subsequent middleware or the request handling process, the middleware catches the exception in the catch block, logs the exception, and returns an appropriate error response to the client.

ASP.NET Framework: In ASP.NET Framework, you can create custom error-handling middleware to handle exceptions that occur during request processing. This middleware can capture and log errors and return appropriate error responses to the client.

Implementation: Error Handling Middleware

// ErrorHandlingMiddleware.cs 
public class ErrorHandlingMiddleware : OwinMiddleware 
{ 
  public ErrorHandlingMiddleware(OwinMiddleware next): base(next) {} 
  public override async Task Invoke (IOwinContext context) 
  { 
    try 
    { 
        await Next.Invoke(context); 
    } 
    catch (Exception ex) 
    {  
        LogException(ex); 
        // Return an appropriate error response to the client
        context.Response.StatusCode = 500; 
        // Internal Server Error 
        context.Response.ContentType = "text/plain"; 
        await context.Response.WriteAsync("An error occurred while processing your request."); 
    } 
  } 
  private void LogException(Exception ex) 
  { 
       // Custom logging logic to log the exception 
  } 
}

Explanation: In ASP.NET Framework, the Error Handling Middleware inherits from ‘OwinMiddleware’. The Invoke method has an ‘IOwinContext’ parameter, which represents the context of the current HTTP request/response. The middleware calls the Next middleware using await Next.Invoke(context); to proceed with the request handling. If an exception occurs during the execution of subsequent middleware or the request handling process, the middleware catches the exception in the catch block, logs the exception, and returns an appropriate error response to the client.

4. Cross-Platform Support and Libraries:

ASP.NET Core:

One of the core design goals of ASP.NET Core is to provide true cross-platform support. It was built from the ground up to be platform-agnostic, allowing it to run on Windows, macOS, and various Linux distributions.
Applications developed on .NET Core can be deployed on different platforms without modification, fostering true portability.
Developers can write code using these cross-platform libraries, ensuring that it can be reused across different operating systems without alteration.

ASP.NET Framework:

Historically, ASP.NET Framework was designed and developed primarily for Windows environments. It tightly integrated with the Windows operating system and relied on Windows-specific components, making it challenging to run on other operating systems.
Libraries developed for .NET Framework are primarily oriented toward the Windows environment and may not be inherently compatible with non-Windows platforms.
To utilize .NET Framework libraries on non-Windows platforms, developers often face compatibility challenges and need to adapt or replace these libraries.

5. JSON Serialization

JSON serialization is a process of converting ASP.NET objects into JSON format (JavaScript Object Notation) and vice versa. Both ASP.NET Core and ASP.NET Framework support JSON serialization, but they use different libraries for this purpose.

ASP.NET Core:

ASP.NET Core introduces built-in JSON serialization using System.Text.Json. This library is part of the ASP.NET Core ecosystem and provides efficient and high-performance JSON serialization and deserialization capabilities. It is designed to be lightweight, fast, and optimized for modern scenarios.
System.Text.Json in ASP.NET Core is optimized for performance and a smaller memory footprint, making it more suitable for high-performance scenarios.

Implementation of JSON Serialization:

using System; 
using System.Text.Json; 
public class Person 
{ 
  public string Name { get; set; } 
  public int Age { get; set; } 
} 
public class Program 
{ 
  public static void Main() 
  { 
      var person = new Person { Name = "John Doe", Age = 30 }; 
      var json = JsonSerializer.Serialize(person); 
      Console.WriteLine(json); 
      // Output: {"Name":"John Doe","Age":30} 
  } 
}

ASP.NET Framework:

In ASP.NET Framework, the default JSON serialization is not built-in, and you need to rely on third-party libraries. The most popular and widely used JSON serialization library in the ASP.NET Framework ecosystem is ‘Newtonsoft.Json’, also known as JsonASP.NET. It is a robust, feature-rich, and well-established library for JSON serialization and deserialization.
It is feature-rich but may have slightly higher performance overhead and memory usage compared to System.Text.Json.
‘Newtonsoft.Json’ is primarily designed for Windows environments, limiting cross-platform capabilities.

If you are migrating from ASP.NET Framework to ASP.NET Core, you may need to update your JSON serialization code to use System.Text.Json instead of ‘Newtonsoft.Json’.

Implementation of JSON Serialization:

using System; 
using Newtonsoft.Json; 
public class Person 
{ 
  public string Name { get; set; } 
  public int Age { get; set; } 
} 
public class Program 
{ 
  public static void Main() 
  { 
      var person = new Person { Name = "John Doe", Age = 30 }; 
      var json = JsonConvert.SerializeObject(person);
      Console.WriteLine(json); 
      // Output: {"Name":"John Doe","Age":30} 
  } 
}

Advantages of ASP.NET Framework:

Mature and Stable: ASP.NET Framework has been around for many years and has undergone extensive testing and improvements. As a result, it is a mature and stable framework with a large community and extensive documentation.
Extensive Class Library: ASP.NET Framework comes with a rich class library (Base Class Library — BCL) that provides a wide range of functionalities, including networking, file I/O, database access, XML manipulation, and more. This extensive library simplifies development and reduces the need for third-party libraries.
Windows-Centric Development: ASP.NET Framework is specifically designed for Windows environments. It integrates well with Windows operating systems and provides access to Windows-specific features, such as Windows Forms, Windows Presentation Foundation (WPF), and Windows Communication Foundation (WCF).
Windows Desktop Applications: If you need to develop traditional Windows desktop applications, ASP.NET Framework offers a robust and well-established platform for building Windows Forms (WinForms) and WPF applications.
ASP.NET Web Forms: ASP.NET Framework includes ASP.NET Web Forms, which allows developers to create web applications using a component-based model. While not as modern as ASP.NET Core, it can still be advantageous for certain legacy projects.
Third-Party Libraries: Over the years, a vast ecosystem of third-party libraries has been developed specifically for ASP.NET Framework. This extensive collection of libraries provides solutions for various use cases and can be beneficial for projects targeting ASP.NET Framework.
Integration with Existing Applications: Many legacy applications and enterprise systems have been built using ASP.NET Framework. If you are maintaining or extending these applications, ASP.NET Framework provides a seamless integration path.
Visual Studio Integration: Visual Studio, the primary Integrated Development Environment (IDE) for ASP.NET development, has excellent support for ASP.NET Framework projects, making it easy to build and debug applications.

Advantages of ASP.NET Core:

Cross-Platform Support: One of the most significant advantages of ASP.NET Core is its cross-platform capability. It can run on multiple operating systems, including Windows, macOS, and various Linux distributions, allowing developers to build applications that are not limited to a single platform.
High Performance: ASP.NET Core is designed for performance. It is lightweight, fast, and optimized for modern workloads. The runtime and libraries have been engineered to deliver superior performance, making it well-suited for high-performance and scalable applications.
Open Source: ASP.NET Core is fully open-source, allowing developers to view, modify, and contribute to the source code. This fosters collaboration and community-driven enhancements, leading to faster improvements and bug fixes.
Lightweight and Modular: ASP.NET Core uses a modular approach, where you can include only the libraries and components that your application requires. This reduces the overall footprint and helps create more efficient, smaller deployments.
Modern Language Features: ASP.NET Core supports C# 8 and later language features, providing access to modern language constructs and functionalities that improve code readability, maintainability, and productivity.
Support for Microservices: ASP.NET Core is well-suited for microservices architecture, where applications are broken down into smaller, independent services. Its lightweight nature and performance make it ideal for building and deploying microservices-based applications.
Cloud-Native Development: With built-in support for cloud-native development, ASP.NET Core fits seamlessly into cloud environments and services. This makes it easier to deploy applications to cloud platforms like Azure.
Single Unified Platform (ASP.NET 5+): Starting from ASP.NET 5, Microsoft has unified ASP.NET Core, ASP.NET Framework, and Xamarin into a single platform called ASP.NET. This convergence simplifies development, and developers can use a unified set of APIs across different application types.
Rapid Development with ASP.NET Core: ASP.NET Core, the web framework built on top of ASP.NET Core, offers a modern, lightweight, and modular approach to web development. It supports Razor Pages, MVC, and Web API, making it versatile for building web applications, APIs, and real-time apps.
Better Dependency Injection Support: ASP.NET Core provides built-in support for Dependency Injection (DI), making it easier to manage and inject dependencies into classes, resulting in more maintainable and testable code.

Wrapping up

In summary, if you prioritize cross-platform compatibility, high performance, and modern development practices, ASP.NET Core is the way to go. On the other hand, if you’re working within a Windows environment, have existing ASP.NET Framework applications, or need to leverage its extensive library ecosystem, ASP.NET Framework remains a valid choice. Your decision should be based on your project’s specific requirements and goals, ultimately aiming to create efficient, scalable, and user-friendly web applications.

Contrasting the Characteristics of ASP.NET Core and ASP.NET Framework

1. Architecture and Compatibility

2. Dependency Injection

3. Middleware

4. Cross-Platform Support and Libraries:

5. JSON Serialization

Written by Mahek Ardeshna