That Pesky “Requested Resource Does Not Support HTTP Method ‘POST’” Error When Using MVC Web API

| January 23, 2013 | in

Software Development Tips & Tricks

While working on a project that involved MVC Web API, I ran into a strange issue. I created my controller, registered my routes and decorated my methods with “[HttpPost]”, but the application would still not allow me to do POST requests to my method (HTTP 405 – Method not allowed. The requested resource does not support http method ‘POST’.).

Here’s the Web API Class I was using:

using System;

 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 using System.Web.Mvc;
 using Eam;
 using HomeBase.Models;

namespace HomeBase.Controllers
 {
 public class CatalogController : ApiControllerBase
 {
 [HttpPost]
 public CatalogItemModel[] GetCatalogItems(string Id)
 {

}
 }

Here’s the route registration I was using:

config.Routes.MapHttpRoute(

 name: "DefaultApi",
 routeTemplate: "api/{controller}/{action}/{id}",
 defaults: new { action = "Index",id = RouteParameter.Optional }
 );

Going crazy? I thought I was too. Turns out both “System.Web.Http” and “System.Web.Mvc” have an “[HttpPost]” attribute. Since this is an API call, I had to use the “[System.Web.Http.HttpPost]” attribute (look closely at your API route registration and note you are calling “MapHttpRoute” and not “MapRoute” like you would for a non-API MVC Controller).

Here’s the new and improved Web API Class:

using System;

 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 using System.Web.Mvc;
 using Eam;
 using HomeBase.Models;

namespace HomeBase.Controllers
 {
 public class CatalogController : ApiControllerBase
 {
 [System.Web.Http.HttpPost]
 public CatalogItemModel[] GetCatalogItems(string Id)
 {