Doing some restapi in VB.Net and stuck on something - vb.net

Question

I doubt anyone has specific experience related to this particular task, but maybe you can spot my problem. I'm trying to make a call to lithium (forum software) to place a vote in their poll, and their docs show this:
Example URL:
http://community.lithium.com/community-name/restapi/vc/polls/id/15/votes/place
Query Arguments:
poll.choice (required): - the choice to place the vote for. The choice is specified by a string of the form id/choice_id where choice_id is the id of the poll choice
Http Method:
POST
So my code looks something like this:
Dim _Response As New XmlDocument
Dim RestApiRoot As String = "http://example.com/community-name/restapi/vc/polls/id/6/votes/place"
APIRequest = WebRequest.Create(RestApiRoot)
APIRequest.Method = "POST"
APIRequest.Headers.Add("poll.choice", HttpContext.Current.Server.UrlEncode("id/" & _choiceID.ToString))
APIResponse = APIRequest.GetResponse()
APIReader = New StreamReader(APIResponse.GetResponseStream())
_Response.LoadXml(APIReader.ReadToEnd())
APIResponse.Close()
I'm not able to successfully register a vote and they say it's because the poll.choice param is not appearing in the header, but if I step through debugging, I see it in the Header Keys/Items just fine.
Anyone have any clue what I might be doing wrong?

Answer 1

I do exactly this with RestSharp, an open source REST framework. It works great with the Lithium REST API.
You're code will look something like this using RestSharp:
You'll create a class to look like the response from the Lithium API, in this case "Response". It will look like this (sorry, you'll have to translate this to VB.NET):
public class LithiumResponse
{
public string status { get; set; }
public string value { get; set; }
public string message { get; set; }
}
Now RestSharp will use that to capture the result like this:
// create the request
var request = new RestRequest();
request.Verb = Method.POST;
request.BaseUrl = "http://example.com/community-name";
// specify the action
request.Action = "restapi/vc/polls/id/6/votes/place";
// add the parameters
request.AddParameter("poll.choice", "id/" + _choiceID.ToString());
// now create a RestClient to execute the request,
// telling it to put the results in your "reponse" class
var client = new RestClient();
var lithiumresponse = client.Execute<LithiumResponse>(request);
// now you can check the status property of your class to
// see if it was successful
if (lithiumresponse.status == "success")
// you successfully placed a vote
I use RestSharp for a lot of interaction with the Lithium API and it makes it brain-dead simple. Pretty awesome library.