Question

I’m sure I’ve done this in another solution, but I can’t seem to find any solution as to do it again and wondered if anyone can help me…

This is my WebAPI code:

public class WebController : ApiController
{
        public void Get(string telephone, string postcode, List<Client> clients)
        {

        }
}

And, calling this from jQuery:

    function Client(name, age) {
            this.Name = name;
            this.Age = age;
    }

    var Clients = [];
    Clients.push(new Client("Chris", 27));

    $.ajax({
        url: "/api/Web/",
        data: { telephone: "999", postcode: "xxx xxx", clients: Clients }
    });

But the “clients” object always comes back as null. I’ve also tried JSON.stringify(Clients), and this is the same result. Can anyone see anything obvious I’m missing here?

Answer 1

The action parameter binding in Web API is different than in ASP.NET MVC (you can read more about it in this article):

• “simple” types (string, int, etc) are bound from the URI
• “complex” types are bound from the request body

If you don’t want to follow the conventions you need to mark your parameters with the [FromBody] or [FromUri] attribute depending from where do you want to bind them.

In you case because you are using a GET request you need to mark your clients param with [FromUri] to bind correctly:

public class WebController : ApiController
{
    public void Get(string telephone, 
                    string postcode, 
                    [FromUri]List<Client> clients)
    {

    }
}