C# Можно ли обойтись без библиотеки?

Question

[Алексей Лебедев]

public static IRestResponse SendSimpleMessage() {
       RestClient client = new RestClient();
       client.BaseUrl = new Uri("https://api.mailgun.net/v3");
       client.Authenticator =
               new HttpBasicAuthenticator("api",
                                          "key-11111111");
       RestRequest request = new RestRequest();
       request.AddParameter("domain",
                            "legends-game.ru", ParameterType.UrlSegment);
       request.Resource = "{domain}/messages";
       request.AddParameter("from", "Excited User <[e-mail]>");
       request.AddParameter("to", "[e-mail]");
       request.AddParameter("subject", "Hello");
       request.AddParameter("text", "Testing some Mailgun awesomness!");
       request.Method = Method.POST;
       return client.Execute(request);
}

Можно без библиотеки что-то такое:

WebRequest request = WebRequest.Create("https://api.mailgun.net/v3");
            request.Method = "GET";
       request.AddParameter("from", "Excited User <[e-mail]>");
       request.AddParameter("to", "[e-mail]");

            WebResponse response = request.GetResponse();
            response.Close();

Answer 1

[Даша Циклаури]

.net 4.5+:

using(var client = new HttpClient()){
  await client.GetAsync();
}

Answer 2

[Андрей Данилов]

Можно.
Раскуривайте класс WebRequest.
Вот, кстати, недавно похожий вопрос был.