asp.net-web-api Quick Start: Working with JSON Return JSON from GET using attributes

Example

1. Setup your formatter and routing in Register of (App_Start/WebApiConfig)

public static class WebApiConfig
{
    public static void Register(HttpConfiguration config)
    {
        GlobalConfiguration.Configuration.Formatters.Clear();
        GlobalConfiguration.Configuration.Formatters.Add(new JsonMediaTypeFormatter());

        config.MapHttpAttributeRoutes();
    }
}

2. Create methods in an ApiController

public class HelloWorldController : ApiController
{
  [HttpGet]
  [Route("echo/{message}")]
  public IHttpActionResult Echo(string message) {
    return Ok(new{ hello: message });  
  }

  [HttpGet]
  [Route("echo/{digits:int}")]
  public IHttpActionResult Echo(int digits) {
    return Ok(new{ hello: digits });  

}

executing GET /echo/foo

{
  "hello": "foo"
}

executing GET /echo/1241290805

{
  "hello": 1241290805
}

as the routing framework takes the most specific conditions (data type) when choosing a method