//Windows SMS API integration code
try

{

    string strResult = "";
    //Prepare you post parameters

    var postValues = new List<KeyValuePair<string, string>>();
    //Your Apikey key

    postValues.Add(new KeyValuePair<string, string>("apikey", "YourApikey"));
    //Approved sender id(6 characters string only).

    postValues.Add(new KeyValuePair<string, string>("senderid", "TESTIN"));
    //Message channel Promotional=1 or Transactional=2.

    postValues.Add(new KeyValuePair<string, string>("channel", "2"));
    //Default is 0 for normal message, Set 8 for unicode sms
     postValues.Add(new KeyValuePair<string, string>("DCS", "0"));
    //Default is 0 for normal sms, Set 1 for immediate display.
     postValues.Add(new KeyValuePair<string, string>("flashsms", "0"));
    //Recipient mobile number (pass with comma seprated if need to send on more then one number).

    postValues.Add(new KeyValuePair<string, string>("mobile", "9999999"));
    //Your message to send.

    string message = HttpUtility.UrlEncode("Test message");

    postValues.Add(new KeyValuePair<string, string>("message", message));
    //Select route

    postValues.Add(new KeyValuePair<string, string>("route","default"));
    

    //Prepare API to send SMS

    Uri requesturl = new Uri("http://login.smsgatewayhub.com/api/mt/SendSMS?");
    //create httpclient request

    var httpClient = new HttpClient();

    var httpContent = new HttpRequestMessage(HttpMethod.Post, requesturl);
    httpContent.Headers.ExpectContinue = false;
    httpContent.Content = new FormUrlEncodedContent(postValues);
    HttpResponseMessage response = await httpClient.SendAsync(httpContent);
    

    //Get response

    var result = await response.Content.ReadAsStringAsync();
    strResult = result.ToString();
    response.Dispose();

    httpClient.Dispose();

    httpContent.Dispose();

}

catch (Exception ex)

{

    throw ex;

}