To send requests and receive responses you can use:
HttpWebRequest req = (HttpWebRequest)WebRequest.Create(url);
where url is the query string "https://...".
The main difference with SSL is you must verify the certificate:
RemoteCertificateValidationCallback remote = ValidateServerCertificate;
ServicePointManager.ServerCertificateValidationCallback = remote;
public bool ValidateServerCertificate(
object sender,
X509Certificate certificate,
X509Chain chain,
SslPolicyErrors sslPolicyErrors)
{
return true;
}