public static void Put(string format) { var id = GetSelectedId(); if (id != Guid.Empty) { var c = new RestSharp.RestClient(String.Format("{0}", baseUrl)); var model = Models.First(user => user.Id == id); model.Name = "RestClient user updated"; c.PutAsync<UserModel>(CreateRequest(Method.PUT, "json").AddBody(model), (resp, result) => WriteResult("PUT", resp)); } }