'Invalid JSON String' for POST request with application/json content type

[dhrushilbadani]

So I was making a POST request to an endpoint that needs application\json. I initialized the RestClient and request and used
request.AddHeader("Content-Type","application/json")
and made subsequent calls to request.AddParameter() but the error I get is Invalid JSON String with a status code of UnsupportedMediaType and also mentions expected application/json or text/json body. Any idea of what's going on?

I tried using a custom serializer as well, but to no avail. The request works successfully on Chrome's Advanced Rest Client.

[behoyh]

I was not able to replicate this issue. Do you have any more information on what you were trying to do?

[dhrushilbadani]

So, I found the workaround -- apparently request.AddParameter("Content-Type", "application/json") does not work, which meant my request body was not in JSON. http://itanex.blogspot.co.at/2012/02/restsharp-and-advanced-post-requests.html had a solution to this. Is there a more 'standard' way to add the Content-type header?

[Danthar]

I have exactly the same problem:

var client = new RestClient(endpoint);

 //client.AddDefaultHeader("Content-Type", "application/json"); //I expect this to be enough
 var req = new RestRequest("api/values");
 req.AddHeader("Content-Type", "application/json"); //but its not so i tried adding it here
 req.AddParameter("application/json", "test", ParameterType.RequestBody); //which didnt work so i tried adding it here
 req.Method = Method.POST;

 var resp = client.Execute(req);

The above described variations of me, trying to send a raw string to a REST api. Do not work.
It does not work, because the RestSharp api does not set the Content-Type header. If i dump the entire request on the server side, it clearly shows that no Content-Type header is set.

I am not sure why this is happening. But it basically bars me from using the library.

[alexeyzimarev]

Thanks for reporting. I think the request format need to be set more conveniently.

[alexeyzimarev]

It is actually all fixed. Use AddJsonBody and both the request format and content type will be set for you