How To Get ASP.NET Web API to Return JSON

first remove xml format :

config.Formatters.Remove(config.Formatters.XmlFormatter);

accepts text/html requests and returns application/json responses :

public class BrowserJsonFormatter : JsonMediaTypeFormatter
    {
        public BrowserJsonFormatter()
        {
            this.SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/html"));
            this.SupportedMediaTypes.Add(new MediaTypeHeaderValue("multipart/form-data"));
            this.SupportedMediaTypes.Add(new MediaTypeHeaderValue("application/json"));
            this.SupportedMediaTypes.Add(new MediaTypeHeaderValue("application/x-www-form-urlencoded"));
            this.SupportedMediaTypes.Add(new MediaTypeHeaderValue("text/plain"));
            this.SerializerSettings.Formatting = Formatting.Indented;
        }

        public override void SetDefaultContentHeaders(Type type, HttpContentHeaders headers, MediaTypeHeaderValue mediaType)
        {
            base.SetDefaultContentHeaders(type, headers, mediaType);
            headers.ContentType = new MediaTypeHeaderValue("application/json");
        }
    }

config.Formatters.Add(new BrowserJsonFormatter());

References
http://stackoverflow.com/questions/9847564/how-do-i-get-asp-net-web-api-to-return-json-instead-of-xml-using-chrome
https://github.com/aspnet/Mvc/issues/1765

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