GSM USSD Modem Request

Question

How can I send a USSD request via GSM modem using c#.

I want to be able to execute any code and the response should come back as an object or string that I can use against a regex

Answer 1

Here is my extract that i have used with the GSM COmm library

   public string SendUssdRequest(string request)
  {
    log.DebugFormat("Sending USSD Request {0}", request);
    string result = "";
    try
    {
        IProtocol protocol = comm.GetProtocol();
        string gottenString = protocol.ExecAndReceiveMultiple("AT+CUSD=1," + request + ",15");
        result = gottenString;
        int i = 0;
        if (!gottenString.Contains("\r\n+CUSD: 2"))
        {
            bool receiving = false;
            do
            {
                receiving = protocol.Receive(out gottenString);
                result += gottenString;
                ++i;
            } while (receiving);
        }

        result = result.Replace("\r\n", "");

        result = result.Replace("+CUSD: 2,", "");
        result = result.Replace(",15", "");
        log.DebugFormat("{1} - USSD Response is:  {0}", result,SenderNumber);
        return result;
    }
    catch(Exception ex) 
    {
        log.Error(ex);
    }
    finally
    {

        comm.ReleaseProtocol();
    }
    return "";
}