REST WEBAPI POST method with parameters not being called - http

Question

I have built a REST API with a controller having a POST method with 4 parameters like this-
[HttpPost]
public void SaveSession([FromBody] string userId, [FromBody] DateTime issueDateTime, [FromBody] string browserType, [FromBody] string salt)
{
// Params need to be changed
_sessionService.SaveSession(userId, issueDateTime, browserType, salt);
}
How should I POST data on the client side, I mean what should be the format of the data to be sent?
I tried this format-
"userId=abc&DateTime=someDatetime&browserType=somebrowser&salt=somesalt"
Its not working if I try this, The web service method is not even being called
Could anyone tell me the correct format?
EDIT:
Here is how I am calling the API-
const string endPoint = #"http://localhost:85/session/Test";
var postData = "userId=abc&DateTime=someDatetime&browserType=somebrowser&salt=somesalt"
var request = (HttpWebRequest) WebRequest.Create(EndPoint + parameters);
request.Method = "POST";
request.ContentLength = 0;
request.ContentType = "application/x-www-form-urlencoded";
if (!string.IsNullOrEmpty(postData) && Method == HttpVerb.POST)
{
var encoding = new UTF8Encoding();
var bytes = Encoding.GetEncoding("iso-8859-1").GetBytes(postData);
request.ContentLength = bytes.Length;
using (var writeStream = request.GetRequestStream())
{
writeStream.Write(bytes, 0, bytes.Length);
}
}
using (var response = (HttpWebResponse) request.GetResponse())
{
var xmlDoc = new XmlDocument();
if (response.StatusCode != HttpStatusCode.OK)
{
var message = String.Format("Request failed. Received HTTP {0}", response.StatusCode);
throw new ApplicationException(message);
}
// grab the response
var responseStream = response.GetResponseStream();
if (responseStream != null)
{
xmlDoc.Load(responseStream);
}
return (xmlDoc);
}
Thanks!

Answer 1

I assume routing has been properly configured.
Said so.... DateTime parameter in the controller method has been named "issueDateTime" while within the request has been named "DateTime".

Answer 2

I got to know, what mistake I was doing. I was sending 4 parameters in a WebService method. We can only send one parameter while calling a web service method. If you want to send multiple data, just send it as an object. Like this -
[HttpPost]
public void SaveSession([FromBody] Values value)
{
var userId = values.userId,
var issueDateTime= values.issueDateTime,
var browserType= values.browserType,
var salt= values.salt,
_sessionService.SaveSession(userId, issueDateTime, browserType, salt);
}