Strongly Typed JSON

Topics: Web Api
Aug 30, 2011 at 8:06 AM
Edited Aug 30, 2011 at 8:07 AM


Today, WCF Web API returns an array of anonymous type as JSON response.


  [{"Id":1,"Name":"First Contact"},{"Id":2,"Name":"Second Contact"},{"Id":3,"Name":"Third Contact"},{"Id":4,"Name":"Fourth Contact"}]


 Is it possible to return array of strong type like -

"contacts" :  [{"Id":1,"Name":"First Contact"},{"Id":2,"Name":"Second Contact"},{"Id":3,"Name":"Third Contact"},{"Id":4,"Name":"Fourth Contact"}]



 I have tried KnownType but it hasn't helped.






Aug 30, 2011 at 2:37 PM
Edited Aug 30, 2011 at 2:39 PM

You can use Json.NET with a custom MediaTypeFormatter and make use of the "TypeNameHandling" feature.

Also, attributes like shown in the link above aren't needed to do this. You can simply set the property on your JsonSerializer ctor.

return new JsonSerializer
                    MissingMemberHandling = MissingMemberHandling.Ignore,
                    ObjectCreationHandling = ObjectCreationHandling.Replace,
                    PreserveReferencesHandling = PreserveReferencesHandling.Objects,
                    ReferenceLoopHandling = ReferenceLoopHandling.Ignore,
                    TypeNameHandling = TypeNameHandling.Objects
Sep 7, 2011 at 10:41 AM


I tried this option. But the output is not what I am expecting.

JSONNet is returning me this output -

[{"$id":"1","$type":"RESTEmptyWebApp.Contact, RESTEmptyWebApp","Name":"First Contact","Id":1},{"$id":"2","$type":"RESTEmptyWebApp.Contact, RESTEmptyWebApp","Name":"Second Contact","Id":2},{"$id":"3","$type":"RESTEmptyWebApp.Contact, RESTEmptyWebApp","Name":"Third Contact","Id":3},{"$id":"4","$type":"RESTEmptyWebApp.Contact, RESTEmptyWebApp","Name":"Fourth Contact","Id":4}]

RESTEmptyWebApp is name of my project. Instead of having an additional $type key, I wanted to have the Object Name as an enclosure for array.


"contacts" :  [{"Id":1,"Name":"First Contact"},{"Id":2,"Name":"Second Contact"},{"Id":3,"Name":"Third Contact"},{"Id":4,"Name":"Fourth Contact"}]

As can be seen, actual array is kept just as it would have served from default JSONhandler. In addition to that I just need "contacts" as enclosure for preceding array.

How to achieve this?