Simple controller which takes POST is not found - asp.net-mvc-4

Question

I've made some previous question asking for the help with the problems since I updated MVC4 webapi beta to RC. I got most in order now, but here's one I cannot figure out the reason for yet.
For this simple controller I have one which accepts a POST and one that accepts GET. When I try to run those by sending request from a HTML form, only the GET controller is found while the POST one will return me the following error.
{
"Message": "No HTTP resource was found that matches the request URI 'http://localhost/webapi/api/play/test'.",
"MessageDetail": "No action was found on the controller 'Play' that matches the name 'test'."
}
Why is the POST controller not found?
Controllers
public class PlayController : ApiController
{
[HttpPost] // not found
public string Test(string output)
{
return output;
}
[HttpGet] // works
public string Test2(string output)
{
return output;
}
}
HTML form
<form action="http://localhost/webapi/api/play/test" method="post">
<input type="text" name="output" />
<input type="submit" name="submit" />
</form>
<form action="http://localhost/webapi/api/play/test2" method="get">
<input type="text" name="output" />
<input type="submit" name="submit" />
</form>

Answer 1

Web.API is a little bit picky when you want to post "simple" values.
You need to use the [FromBody] attribute to signal that the value is not coming from the URL but from the posted data:
[HttpPost]
public string Test([FromBody] string output)
{
return output;
}
With this change you won't get 404 anymore but output will be always null, because Web.Api requries the posted values in special format (look for the Sending Simple Types section):
Second, the client needs to send the value with the following format:
=value
Specifically, the name portion of the name/value pair must be empty for a simple type. Not >all browsers support this for HTML forms,
but you create this format in script...
So recommend that you should create a model type:
public class MyModel
{
public string Output { get; set; }
}
[HttpPost]
public string Test(MyModel model)
{
return model.Output;
}
Then it will work with your sample froms without modifing your views.