Find the best tutors and institutes for .NET MVC

Find Best .NET MVC

Please select a Category.

Please select a Locality.

No matching category found.

No matching Locality found.

Outside India?

Search for topics

ASP.NET Web API 2 action method return types

Sachin Kumar
04/07/2017 0 0

Here, in this article we will learn ASP.NET Web API 2 action method return types.

A Web API 2 action method return types can be any of the following :

  • Void
  • HttpResponseMessage
  • IHttpActionResult
  • Other type or Complex type




A Web API 2 action method return types can be any of the following

Void

When an ASP.NET Web API return type is void, it will return an empty HTTP response.

In the following example a web API with void return:

Example

public class SampleController : ApiController
{
  public void Post()
   {
            
   }
}

Note: We are using fiddler to call Web API, it is a free web debugging proxy which logs all HTTP(s) traffic between your computer and the Internet



Result

Calling sample web API in fiddler
Web API 2 action method void return 


It is returning status code 204 No Content (an empty HTTP response)
Web API 2 action method void return status code 204 No Content (an empty HTTP response) 





 

HttpResponseMessage

  • When Web API return type is HttpResponseMessage, Web API converts the return value directly into an HTTP response message.
  • We can set the status code, content as per our requirement.

 

In the following example a web API with HttpResponseMessage return:

Example

public HttpResponseMessage Get()
{
    HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, "value1");            
    return response;
}


Result

Calling sample Web API with HTTP GET request
Web API 2 action method HttpResponseMessage return 


In Response, It is returning status code 200 OK and Content
Web API 2 action method void return status code 204 No Content (an empty HTTP response) 



Note:Web API serialized model into the response body based on request header formatter



In the following example a web API return HttpResponseMessage with list of Countries in response body:

Example

public HttpResponseMessage Get()
{
   // list of Countries
   List Countries = new List();
    Country country = new Country();
    country.ID = 1;
    country.CountryName = "USA";
    country.Capital = "Washington";
    Countries.Add(country);
        
    //Countries to the response body.             
    HttpResponseMessage response = Request.CreateResponse(HttpStatusCode.OK, Countries);            
    return response;
}


Result

In Response, It is returning status code 200 OK and Content
Web API 2 action method HttpResponseMessage return 






IHttpActionResult

IHttpActionResult is introduced in Web API 2, IHttpActionResult interface acts like a factory for HttpResponseMessage.

There are some advantages of using the IHttpActionResult over HttpResponseMessage

  • The code is cleaner and easier to read
  • Unit testing for controller action methods become easy
  • It comes with custom built in responses
    • Ok
    • NotFound
    • Exception
    • Unauthorized
    • BadRequest
    • Conflict
    • Redirect

In the following example a web API return IHttpActionResult with list of Countries in response body:

Example

public IHttpActionResult Get(int id)
{
   // list of Countries
   List Countries = new List();
    Country country = new Country();
    country.ID = 1;
    country.CountryName = "USA";
    country.Capital = "Washington";
    Countries.Add(country);
    
    //finding country based on provided id
    var result = Countries.FirstOrDefault(x=> x.ID ==id);
    if (result == null)
    {
        //create a 404 (Not Found) response
        return NotFound();                
    }
    else
    {
        //creates a 200 (OK) response that contains the country
        return Ok(result);
    }
}





Result

Calling sample web API with HTTP GET request and id
Web API 2 action method HttpResponseMessage return 


In Response, It is returning status code 200 OK and Content
Web API 2 action method HttpResponseMessage return 


Calling sample web API with HTTP GET request and id(which is not exist)
Web API 2 action method HttpResponseMessage return 


In Response, It is returning status code 404 Not Found
Web API 2 action method HttpResponseMessage return 






 

Other type or Complex type

  • A Web API can return other or custom complex type
  • Web API serialize value and return it into the response body
  • The response status code 200 OK
  • But in this approach we cannot directly return an error code, still we can throw an HttpResponseException for error codes

In the following example a web API with Complex return type:

Example

public class CountryController : ApiController
{
    public IEnumerable Get()
    {
        List Countries = new List();
        Country country = new Country();
        country.ID = 1;
        country.CountryName = "USA";
        country.Capital = "Washington";
        Countries.Add(country);
        return Countries;
    }
}

Result

Calling Country web API with HTTP GET request
Web API 2 action method Complex return type 


In Response, It is returning status code 200 OK and Content
Web API 2 action method void return status code 204 No Content (an empty HTTP response) 
0 Dislike
Follow 0

Please Enter a comment

Submit

Other Lessons for You

Clear boostrap modal on hide or close
When I am working with MVC project I had a requirement like to clear all the errors and text entered inside a bootstrap modal. So that when I opened the modal again I could see a plain binding. $("#myModal").on("hidden.bs.modal",...

Dorababu Meka | 06 Sep

0 0
0

C# (Sharp) Syllabus
C# (Sharp) Syllabus: C# (Sharp) Syllabus Lesson 01: Getting Started Lesson 02: Expressions, Types, and Variables Lesson 03: Control Statements - Selection Lesson 04: Control...

Arvind Yadav | 12 Mar

1 0
0

.NET With AngularJS Training Program Syllabus
What You will Learn in .NET with AngularJS Training Program? Introduction to .Net: Features of .Net, CTS, CLS, CLR and MSIL. C# & .Net Basics and Branching & Flow Control. OOPs Concepts,...

DeCode Classes | 18/12/2017

0 0
0

Angular-2 Developer Training Program Syllabus
Angular2 Developer Training Program Syllabus: Introduction to Angular2. Why Angular2. Angular2 Features: Components, Services and Typescript. Angular2 Components: Templates, Modules, Services...

DeCode Classes | 11/12/2017

0 0
0

Pro Developer Program Syllabus
What you will learn in Pro-Developer Program: i. Introduction to Web Technologies. ii. Introduction to .Net - Features of .Net, CTS, CLS, CLR and MSIL. iii. C# & .Net Basics - Data Types,...

DeCode Classes | 23/11/2017

1 0
0

Find Best .NET MVC ?

Find Now »

UrbanPro.com is India's largest network of most trusted tutors and institutes. Over 25 lakh students rely on UrbanPro.com, to fulfill their learning requirements across 1,000+ categories. Using UrbanPro.com, parents, and students can compare multiple Tutors and Institutes and choose the one that best suits their requirements. More than 6.5 lakh verified Tutors and Institutes are helping millions of students every day and growing their tutoring business on UrbanPro.com. Whether you are looking for a tutor to learn mathematics, a German language trainer to brush up your German language skills or an institute to upgrade your IT skills, we have got the best selection of Tutors and Training Institutes for you. Read more