HTTP Send SMS API using C#

//Your authentication key

string authKey = "YourAuthKey";
//Multiple mobiles numbers separated by comma

string mobileNumber = "9999999";
//Sender ID,While using route4 sender id should be 6 characters long.

string senderId = "102234";
//Your message to send, Add URL encoding here.

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


//Prepare you post parameters

StringBuilder sbPostData = new StringBuilder();

sbPostData.AppendFormat("authkey={0}", authKey);

sbPostData.AppendFormat("&mobiles={0}", mobileNumber);

sbPostData.AppendFormat("&message={0}", message);

sbPostData.AppendFormat("&sender={0}", senderId);

sbPostData.AppendFormat("&route={0}", "default");


try

{

    //Call Send SMS API

    string sendSMSUri = "http://api.msg91.com/api/sendhttp.php";
    //Create HTTPWebrequest

    HttpWebRequest httpWReq = (HttpWebRequest)WebRequest.Create(sendSMSUri);
    //Prepare and Add URL Encoded data

    UTF8Encoding encoding = new UTF8Encoding();

    byte[] data = encoding.GetBytes(sbPostData.ToString());
    //Specify post method

    httpWReq.Method = "POST";

    httpWReq.ContentType = "application/x-www-form-urlencoded";

    httpWReq.ContentLength = data.Length;
    using (Stream stream = httpWReq.GetRequestStream())

    {

    	stream.Write(data, 0, data.Length);

    }
    //Get the response

    HttpWebResponse response = (HttpWebResponse)httpWReq.GetResponse();

    StreamReader reader = new StreamReader(response.GetResponseStream());

    string responseString = reader.ReadToEnd();

    
    //Close the response

    reader.Close();

    response.Close();

}

catch (SystemException ex)

{

	MessageBox.Show(ex.Message.ToString());

}