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Ketan Chavda
Ketan Chavda

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.Net For Web API - Everything You Need To Know

The software development is not just an expensive affair, while it’s technically complex as well. The development involves a lot of nitty-gritty tasks that eat up a large amount of time. Thanks to APIs which allow the developers to integrate two different parts of the applications or two separate applications through various protocols, tools, and resources that makes web application development plain-sailing.

Under the API landscape, there are different types of API, which works at the operating system level, define the software libraries behavior and the web API.

Here, we will dig deep inside at what web API is:

The web API is also referred to as a web server that provides an interface where the communication takes place leveraging web-specific protocols and internet. The web API makes the resources appear local to internet users by allowing them to store the content online. The web APIs that defines a set of endpoints, response structure, and request messages are served through an HTTP interface and used a standard approach to find out the response media types.

The different types of technology stacks are used to create web APIs, namely- Java, .NET, PHP, and others. Among all, ASP.NET technology is popular among Web developers to build a web API.

Take a glance at ASP.NET API:

The ASP.NET API is a framework that’s highly used to create HTTP services which can be easily accessed in different applications on a wide range of client machines including browsers, web, and mobile devices. Except sending data as response and supporting only HTTP protocol, the ASP.NET web API works similar to ASP.NET MVC application.

The ASP.NET web communicate with different devices from a single database, API includes HttpClient to communicate with web API server, can be self-hosted or hosted in IIS, support different forms of response data (JSON, XML, and others), and ASP.NET request/response pipeline that makes it an ideal platform to build RESTful services, AJAX-based web applications, and back-end for native mobile applications.

Still, not convinced? Need more reasons on why to use .NET for creating web API? Here’s the answer:

  • The endpoints automatically serialize the class to properly formatted response data type with no additional configuration required. Besides, the serialization customization for endpoints facilitates serving unique web development needs that further helps in delivering modern web experiences.

  • The built-in support for JSON web tokens makes the API endpoints secure. By defining the access control rules in the code, the policy-based authorization and authentication can be enabled.

  • Defining routes alongside the coding is feasible with ASP.NET development services. The query string, data from the request path, and request body bound to method parameters.

  • The support for HTTPS allows the developers to run, test, debug, and deploy the app securely by enabling local HTTPs and generating test certificate.

In this manner, ASP.NET web API provides a set of default options, and extensible infrastructure that meet the demands of varied types of modern development needs such as high compatibility with all the browsers and mobile devices. Twitter, Facebook, and Google are some of the savvy leaders that are using web API to power web applications and mobile applications.

Geared up to build the flexible framework- ASP.NET web API for building HTTP based endpoints and client? If so, we have covered the need in the next section.

How to create ASP.NET web API?

Before heading to the step-by-step tutorial for building web API using ASP.NET, take a look at the software prerequisites that are Visual studio 2019, ASP.NET, C#, SQL server, and WideWorldImporters database.

Now, let’s get started:

  • Create a project

Open the visual studio and perform the following steps to create a new blank project.

Go to File -> New -> Project, then select installed and go to Installed > Visual C# > Web > .NET Core. Post-selection, give a name to the project and click OK.

A new model dialog will appear, where you have to select web API and then click OK that will prepare all the initial files for the project. Finally, the project file created can be reviewed or browsed in solution explorer.

  • Install NuGet

The next step is to install NuGet packages that can be installed by using a couple of commands from the package manager console.

Install-Package Microsoft.AspNet.WebApi

Install-Package Microsoft.Owin.Host.SystemWeb

Install-Package Microsoft.AspNet.WebApi.OwinSelfHost

  • Add model

In the solution explorer, go to model folder > Add > Class, and then give a name to the class to make it ready for use. Later, add all the fields to the model.

  • Add controller

The controller in the web API is essentially an object that handles HTTP requests and it’s created by default, so if you require a new controller with a different name, then you have to create it.

In solution explorer, go to controllers > Add > controller > Web API 2 controller-Empty template. Later, click the add button to add the controller and give a suitable name to it. The successfully created controller handles all the CRUD functions and a namespace will be added to the class.

A GET method is written and added in the controller class to respond to the GET HTTP verb.

  • Set up dependency injection

ASP.NET excels at enabling dependency injection natively that eliminate the need for using third-party frameworks to inject dependencies in controllers. ASP.NET project template has a class named Startup where the configuration to inject instances such as repositories, DBContext, and loggers are added. The configure method aids in adding the configuration for HTTP request runtime.

  • Run web API

Now, build the solution and run it. Click F5 to start debugging for the web API project and when everything works fine, the output will appear in the browser at your localhost in available port. Thereafter, the web API services can be deployed on a local dedicated server using IIS to keep it running as service. Open the IIS, and on the left side under sites, go to add a new website and provide all the details including site name, physical path, and binding. Finally, the web API will run on the webserver.

  • Test the API

Testing is all-important to see the output that web API produce in the browser. Open the web API methods- which is created for the webserver in your browser to see the results.

Also Read: The Prominence of 7 PHP Frameworks In Modernizing The Web Presence


Do you want to build a web API using .NET? Are you creating a new API or a rookie player who is attempting to create an API for the first time? If so, the article is certainly your piece of cake that helps right from understanding why to leverage ASP.NET to how to embrace the technology for building a web API with all the nitty-gritty details included. Let’s dive in!

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