Web api should return JSon by default [duplicate]

Question

This is what I have currently

GlobalConfiguration.Configuration.Formatters.JsonFormatter.MediaTypeMappings.Add(new QueryStringMapping("type", "json", new MediaTypeHeaderValue("application/json")));             

GlobalConfiguration.Configuration.Formatters.XmlFormatter.MediaTypeMappings.Add(new QueryStringMapping("type", "xml", new MediaTypeHeaderValue("application/xml")));

it works fine when I call API with query like this

for xml : http://localhost:49533/api/?type=xml
for json: http://localhost:49533/api/?type=json

but what I want is JSON by default? is that possible? I want above options available as well

Answer 1

Content negotiation looks at several things in your request including the Accept header (but also the contenttype header to infer returned results). If your request has XML in the accept header then it will go to XML.

Below is the chrome default headers, note that it's asking for XML, hence Web API will return XML by default for chrome.

{Connection: keep-alive Accept: text/html, application/xhtml+xml, application/xml; q=0.9, image/webp, /; q=0.8 Accept-Encoding: gzip, deflate, sdch Accept-Language: en-US, en; q=0.8 Host: localhost:63586 User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/33.0.1750.117 Safari/537.36 }

You can choose in your application to ignore the accept headers, by removing them from the formatters:

config.Formatters.JsonFormatter.MediaTypeMappings.Clear();

Then add your query mapping (similarly of course for the XML formatter).