How to add Web API to an existing ASP.NET MVC 4 Web Application project?

Question

I wish to add an ASP.NET Web API to an ASP.NET MVC 4 Web Application project, developed in Visual Studio 2012. Which steps must I perform to add a functioning Web API to the project? I'm aware that I need a controller deriving from ApiController, but that's about all I know.

Let me know if I need to provide more details.

aknuds1 · Accepted Answer · 2015-10-16 06:38:15Z

The steps I needed to perform were:

Add reference to System.Web.Http.WebHost.
Add App_Start\WebApiConfig.cs (see code snippet below).
Import namespace System.Web.Http in Global.asax.cs.
Call WebApiConfig.Register(GlobalConfiguration.Configuration) in MvcApplication.Application_Start() (in file Global.asax.cs), before registering the default Web Application route as that would otherwise take precedence.
Add a controller deriving from System.Web.Http.ApiController.

I could then learn enough from the tutorial (Your First ASP.NET Web API) to define my API controller.

App_Start\WebApiConfig.cs:

using System.Web.Http; class WebApiConfig { public static void Register(HttpConfiguration configuration) { configuration.Routes.MapHttpRoute("API Default", "api/{controller}/{id}", new { id = RouteParameter.Optional }); } }

Global.asax.cs:

using System.Web.Http; ... protected void Application_Start() { AreaRegistration.RegisterAllAreas(); RegisterGlobalFilters(GlobalFilters.Filters); WebApiConfig.Register(GlobalConfiguration.Configuration); RegisterRoutes(RouteTable.Routes); BundleConfig.RegisterBundles(BundleTable.Bundles); }

Update 10.16.2015:

Word has it, the NuGet package Microsoft.AspNet.WebApi must be installed for the above to work.

This was really helpful. I had to add a reference to System.Net.Http as well, but apart from that, it worked like a charm! — Christofer Eliasson, CommentedAug 24, 2012 at 13:06
I upgraded a project from MVC3 to 4 as well and also needed to add a reference to System.Web.Http. — Damien Sawyer, CommentedOct 16, 2012 at 22:16
You can use nuget now, and stay on top of any changes that happen! nuget.org/packages/Microsoft.AspNet.WebApi — Christopher, CommentedAug 13, 2013 at 2:25
I wouldn't get this to work until I changed my web api register to: GlobalConfiguration.Configure(WebApiConfig.Register); — KingOfHypocrites, CommentedJul 14, 2014 at 12:10
@LuisGouveia I guess it's to late but someone else will probably resolve it quicker if this is what I had. GlobalConfiguration.Configure(WebApiConfig.Register); in Global.asax goes before RouteConfig.RegisterRoutes(RouteTable.Routes); — Maxim, CommentedJan 6, 2015 at 19:11

Hakan Fıstık · Accepted Answer · 2019-03-05 09:39:23Z

To add WebAPI in my MVC 5 project.

Open NuGet Package manager console and run

PM> Install-Package Microsoft.AspNet.WebApi

Add references to System.Web.Routing, System.Web.Net and System.Net.Http dlls if not there already
Right click controllers folder > add new item > web > Add Web API controller
Web.config will be modified accordingly by VS

Add Application_Start method if not there already

protected void Application_Start() { //this should be line #1 in this method GlobalConfiguration.Configure(WebApiConfig.Register); }

Add the following class (I added in global.asax.cs file)

public static class WebApiConfig { public static void Register(HttpConfiguration config) { // Web API routes config.MapHttpAttributeRoutes(); config.Routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); } }

Modify web api method accordingly

namespace <Your.NameSpace.Here> { public class VSController : ApiController { // GET api/<controller> : url to use => api/vs public string Get() { return "Hi from web api controller"; } // GET api/<controller>/5 : url to use => api/vs/5 public string Get(int id) { return (id + 1).ToString(); } } }

Rebuild and test

Build a simple html page

<html xmlns="http://www.w3.org/1999/xhtml"> <head> <title></title> <script src="../<path_to_jquery>/jquery-1.9.1.min.js"></script> <script type="text/javascript"> var uri = '/api/vs'; $(document).ready(function () { $.getJSON(uri) .done(function (data) { alert('got: ' + data); }); $.ajax({ url: '/api/vs/5', async: true, success: function (data) { alert('seccess1'); var res = parseInt(data); alert('got res=' + res); } }); }); </script> </head> <body> .... </body> </html>

The point that created a difference was placing the WebApiconfig.Register in the first line, as was mentioned by @kheya — Rajat, CommentedJan 16, 2018 at 9:35
I would like to add, your api controller name have to end with Controller, like CarController (not just Car)!!! So many people forget about it and obtain error message "No type was found that matches the controller named {0}'" — 1_bug, CommentedAug 24, 2018 at 10:39
To be more efficient with this nice answer you can disregard steps 4, 8 and 9. (they are not so essential) And if you swap the order of step 5 and 6 they will make more sense (it is better to create a class then use it, instead of use the class then create it) — Hakan Fıstık, CommentedMar 5, 2019 at 11:38
Where exactly are we adding references to System.Web.Routing, System.Web.Net and System.Net.Http? — gabed123, CommentedMar 7, 2019 at 23:04

itzmebibin · Accepted Answer · 2016-09-21 06:42:29Z

UPDATE 11/22/2013 - this is the latest WebApi package:

Install-Package Microsoft.AspNet.WebApi

Original answer (this is an older WebApi package)

Install-Package AspNetWebApi

More details.

As of 2013 that is a legacy package and you want Install-Package Microsoft.AspNet.WebApi now. See nuget.org/packages/Microsoft.AspNet.WebApi — Christopher, CommentedAug 13, 2013 at 2:24

Teoman shipahi · Accepted Answer · 2014-07-22 05:13:11Z

As soon as you add a "WebApi Controller" under controllers folder, Visual Studio takes care of dependencies automatically;

Visual Studio has added the full set of dependencies for ASP.NET Web API 2 to project 'MyTestProject'.
The Global.asax.cs file in the project may require additional changes to enable ASP.NET Web API.
Add the following namespace references:
using System.Web.Http; using System.Web.Routing;
If the code does not already define an Application_Start method, add the following method:
protected void Application_Start() { }
Add the following lines to the beginning of the Application_Start method:
GlobalConfiguration.Configure(WebApiConfig.Register);

Does not work here. 1. Nuget: Install-Package Microsoft.AspNet.WebApi 2. Add new item "Web API Controller Class (v2.1)". Result: adds the api controller but does not change Application_Start. With Owin. — Artyom, CommentedJul 31, 2015 at 11:03
this is the right answer when you have vs2015 - update 3 and adding web api 2 controller. — ModChowdhury, CommentedMay 15, 2017 at 9:58
It did in 2017, but I had to upgrade my WebApi assemblies. I also had to create the WebApiConfig class manually, learn.microsoft.com/en-us/aspnet/web-api/overview/advanced/… — johnny, CommentedDec 6, 2018 at 16:45

cuongle · Accepted Answer · 2015-06-03 21:51:22Z

22

You can install from nuget as the the below image:

enter image description here

Or, run the below command line on Package Manager Console:

Install-Package Microsoft.AspNet.WebApi

edited Jun 3, 2015 at 21:51

answered Aug 16, 2012 at 15:25

cuongle

75.4k30 gold badges154 silver badges212 bronze badges

3
So, what else do I need to do except add the controller? This is why I posted this question in the first place, the tutorial doesn't really say since it assumes a Web API project. I've added an API controller, but it isn't routed to.
– aknuds1
CommentedAug 17, 2012 at 6:57
1
The tutorial wasn't of much help as regards adding a Web API to an existing project, so I figured it out from a Web API project, as outlined in my answer.
– aknuds1
CommentedAug 17, 2012 at 7:34
I agree, it seems that this plumbing is already installed if you use the Web App project template.
– longda
CommentedFeb 8, 2013 at 22:56
@cuongle : web api version 2.2 will be install with mvc 4 ? does it support MVC 4?
– Thomas
CommentedNov 30, 2015 at 11:00

Add a comment |

Community · Accepted Answer · 2017-05-23 12:34:44Z

Before you start merging MVC and Web API projects I would suggest to read about cons and pros to separate these as different projects. One very important thing (my own) is authentication systems, which is totally different.

IF you need to use authenticated requests on both MVC and Web API, you need to remember that Web API is RESTful (don't need to keep session, simple HTTP requests, etc.), but MVC is not.

To look on the differences of implementations simply create 2 different projects in Visual Studio 2013 from Templates: one for MVC and one for Web API (don't forget to turn On "Individual Authentication" during creation). You will see a lot of difference in AuthencationControllers.

So, be aware.

Hakan Fıstık · Accepted Answer · 2019-03-09 06:55:07Z

NOTE : this is just an abbreviation of this answer above

Open NuGet Package manager console and run

PM> Install-Package Microsoft.AspNet.WebApi

Add references to System.Web.Routing, System.Web.Net and System.Net.Http dlls if not there already

Add the following class

public static class WebApiConfig { public static void Register(HttpConfiguration config) { // Web API routes config.MapHttpAttributeRoutes(); config.Routes.MapHttpRoute( name: "DefaultApi", routeTemplate: "api/{controller}/{id}", defaults: new { id = RouteParameter.Optional } ); } }

Add Application_Start method if not there already (in global.asax.cs file)

protected void Application_Start() { //this should be line #1 in this method GlobalConfiguration.Configure(WebApiConfig.Register); }

Right click controllers folder > add new item > web > Add Web API controller

namespace <Your.NameSpace.Here> { public class VSController : ApiController { // GET api/<controller> : url to use => api/vs public string Get() { return "Hi from web api controller"; } } }

Where exactly are we adding references to System.Web.Routing, System.Web.Net and System.Net.Http? — gabed123, CommentedMar 7, 2019 at 23:08
From the Add Reference Dialog, open that dialogue and search for the names of those assemblies, there is a great chance that they are already added. (but just to make sure) — Hakan Fıstık, CommentedMar 8, 2019 at 5:34
Is the Application_Start method supposed to be a part of the global class in Global.asax.cs? — gabed123, CommentedMar 8, 2019 at 17:55
yes, I updated my answer to demonstrate that, that you for the note — Hakan Fıstık, CommentedMar 9, 2019 at 6:54

Hakan Fıstık · Accepted Answer · 2020-02-15 07:58:06Z

3

The above solution works perfectly. I prefer to choose Web API option while selecting the project template as shown in the picture below

Note: The solution works with Visual Studio 2013 or higher. The original question was asked in 2012 and it is 2016, therefore adding a solution Visual Studio 2013 or higher.

edited Feb 15, 2020 at 7:58

Hakan Fıstık

19.7k16 gold badges124 silver badges150 bronze badges

answered Apr 21, 2016 at 14:29

Sankar Krishnamoorthy

1,33513 silver badges19 bronze badges

2
If you are creating a project that involves Web API, it would be easier to choose the Web API option. The option will create all required files as mentioned in the above replies.
– Sankar Krishnamoorthy
CommentedApr 25, 2016 at 11:30
The problem at hand here is in Visual studio 2012 and mvc 4. Although your solution is just fine, you cannot do it in that way in VS 2012
– netfed
CommentedJul 6, 2016 at 16:11
This is a good point and I have tried above solution with VS 2013. Thanks @netfed for pointing out.
– Sankar Krishnamoorthy
CommentedJul 6, 2016 at 23:56
Hi All, I've got the API element working in my MVC solution, but as default it tried to run the solution as a API solution. But I want it to run as a MVC solution as default and then if you go to the API location etc, run the APIs.. Has anyone else had this issue and been able to resolve it? Thanks
– Chris Cooper
CommentedFeb 20, 2017 at 11:48
"to an existing ASP.NET MVC 4 Web Application"
– Ali123
CommentedApr 1, 2021 at 5:02

Add a comment |

iDeveloper · Accepted Answer · 2019-05-22 06:28:50Z

I had same problem, the solution was so easy

Right click on solotion install Microsoft.ASP.NET.WebApi from "Manage Nuget Package for Sulotion"

boom that's it ;)

Collectives™ on Stack Overflow

How to add Web API to an existing ASP.NET MVC 4 Web Application project?

9 Answers 9

Linked

Hot Network Questions

Collectives™ on Stack Overflow

9 Answers 9

Linked

Related