WebApiContrib.Formatting.Jsonp

WebApiContrib.Formatting.Jsonp provides a JSONP MediaTypeFormatter implementation for ASP.NET Web API.

In order to add it to your Web API solution, run Install-Package WebApiContrib.Formatting.Jsonp from your NuGet Package Manager console in Visual Studio.

To use the JsonpMediaTypeFormatter, add the following code to your Web API Configuration:

FormatterConfig.RegisterFormatters(GlobalConfiguration.Configuration.Formatters);

The FormatterConfig class looks this:

public class FormatterConfig
{
    public static void RegisterFormatters(MediaTypeFormatterCollection formatters)
    {
        var jsonFormatter = formatters.JsonFormatter;
        jsonFormatter.SerializerSettings = new JsonSerializerSettings
        {
            ContractResolver = new CamelCasePropertyNamesContractResolver()
        };

        // Insert the JSONP formatter in front of the standard JSON formatter.
        var jsonpFormatter = new JsonpMediaTypeFormatter(formatters.JsonFormatter);
        formatters.Insert(0, jsonpFormatter);
    }
}

After that, update your Default ASP.NET Web API route in /App_Start/RouteConfig.cs:

routes.MapHttpRoute(
    name: "DefaultApi",
    routeTemplate: "api/{controller}/{id}/{format}",
    defaults: new { id = RouteParameter.Optional, format = RouteParameter.Optional }
);

Now you should be able to issue JSONP requests against your Web API.

To see the JsonpMediaTypeFormatter in action, just clone this project, run the WebContribContrib.Formatting.Jsonp.SampleWebHost project web application, and then start the WebApiContrib.Formatting.Jsonp.SampleJQueryClient web application and hit the "Get JSONP" button.