Append URL Query Strings to request - restsharp

Question

I'm trying to send a POST request and format the query string in a specific format. Order doesn't matter aside from the first parameter, but I haven't been successful.
What I need:
localhost/someapp/api/dosomething/5335?save=false&userid=66462
What some of my attempts have spit out:
http://localhost/someapp/api/dosomething/?Id=29455&save=false&userId=797979
http://localhost/someapp/api/dosomething/?save=false&userId=797979
How I formatted the request:
request.AddQueryParameter("Id", "29455");
request.AddQueryParameter("save", "false");
request.AddQueryParameter("user", "4563533245");
If I try AddParameterfor Id it doesn't get appended on the query string (I'm thinking because it's a POST and not a GET), so that won't work. The API isn't expecting a form, it's expecting :
(string id, List<Dictionary<string,string>>)
I could use a StringBuilder, but that feels wrong. I'm not sure if UrlSegment is the best way to go either, since I would basically be hacking the query string. Is there a way to format my request in the format I need using RestSharp's API?

Answer 1

What I ended up using is UrlSegment and then kept the .AddQueryParameter methods, so the final code block looks like :
var url = new RestClient(localhost/someapp/api/dosomething/{id});
var request = new RestRequest(Method.POST);
request.AddParameter("Id", "5335", ParameterType.UrlSegment);
request.AddQueryParameter("save", "true");
request.AddQueryParameter("UserId", "5355234");
Which produced the URI I needed.

Answer 2

The easiest coding process for using RestSharp or any other API client library would be to use Postman to generate if you are unsure of how to code it. Download Postman, do a new request, enter the URL string to send to the API, click on Code, select C# (RestSharp) from the dropdown. Here is the code it generated.
var client = new RestClient("http://localhost/someapp/api/dosomething /5335?save=false&userid=66462");
var request = new RestRequest(Method.POST);
request.AddHeader("Postman-Token", "bd05aa45-f1b9-4665-a3e7-888ad16f2800");
request.AddHeader("cache-control", "no-cache");
IRestResponse response = client.Execute(request);