Sending group sms from pc to mobiles using c#
<p>I am able to send an sms from computer to mobile, but i am not able to send multiple sms from pc.
This code is running successfully, i am sending message through AT Commands, i have searched google and even in stackoverflow, the information given is not matching with my requirements, so i am writing the code below, if you can give me some suggestions, please tell me. If any additional questions you want to ask me then do let me know please.</p>

<p>SMSForm.cs file</p>

<pre><code>using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.IO;
using System.IO.Ports;
using Queue.Classes;

namespace Queue
{
public partial class SmsForm : Form
{
    public SmsForm()
    {
        InitializeComponent();
    }
    #region Private Variables

    SerialPort port = new SerialPort();
    clsSMS objclsSMS = new clsSMS();
    ShortMessageCollection objShortMessageCollection = new ShortMessageCollection();
    #endregion

    #region Private Methods

    #region Write StatusBar
    private void WriteStatusBar(string status)
    {

            statusBar1.Text = "Message: " + status;


    }
    #endregion

    #endregion



    private void btnOK_Click(object sender, EventArgs e)
    {
        try
        {
            //Open communication port 
            this.port = objclsSMS.OpenPort(this.cboPortName.Text, Convert.ToInt32(this.cboBaudRate.Text), Convert.ToInt32(this.cboDataBits.Text), Convert.ToInt32(this.txtReadTimeOut.Text), Convert.ToInt32(this.txtWriteTimeOut.Text));

            if (this.port != null)
            {
                this.gboPortSettings.Enabled = false;

                //MessageBox.Show("Modem is connected at PORT " + this.cboPortName.Text);
                this.statusBar1.Text = "Modem is connected at PORT " + this.cboPortName.Text;

                //Add tab pages
                this.tabSMSapplication.TabPages.Add(tabPage2);
                //  this.tabSMSapplication.TabPages.Add(tbReadSMS);
                //  this.tabSMSapplication.TabPages.Add(tbDeleteSMS);

                this.lblConnectionStatus.Text = "Connected at " + this.cboPortName.Text;
                this.btnDisconnect.Enabled = true;
            }

            else
            {
                //MessageBox.Show("Invalid port settings");
                this.statusBar1.Text = "Invalid port settings";
            }
        }
        catch (Exception ex)
        {
            ErrorLog(ex.Message);
        }
    }

    private void SmsForm_Load(object sender, EventArgs e)
    {
        try
        {
            #region Display all available COM Ports
            string[] ports = SerialPort.GetPortNames();

            // Add all port names to the combo box:
            foreach (string port in ports)
            {
                this.cboPortName.Items.Add(port);
            }
            #endregion

            //Remove tab pages
            this.tabSMSapplication.TabPages.Remove(tabPage2);

            //  this.tabSMSapplication.TabPages.Remove(tbReadSMS);
            //   this.tabSMSapplication.TabPages.Remove(tbDeleteSMS);

            this.btnDisconnect.Enabled = false;
        }
        catch (Exception ex)
        {
            ErrorLog(ex.Message);
        }
    }

    private void btnDisconnect_Click(object sender, EventArgs e)
    {
        try
        {
            this.gboPortSettings.Enabled = true;
            objclsSMS.ClosePort(this.port);

            //Remove tab pages
            this.tabSMSapplication.TabPages.Remove(tabPage2);
            //    this.tabSMSapplication.TabPages.Remove(tbReadSMS);
            //    this.tabSMSapplication.TabPages.Remove(tbDeleteSMS);

            this.lblConnectionStatus.Text = "Not Connected";
            this.btnDisconnect.Enabled = false;

        }
        catch (Exception ex)
        {
            ErrorLog(ex.Message);
        }
    }




    #region Error Log
    public void ErrorLog(string Message)
    {
        StreamWriter sw = null;

        try
        {
            WriteStatusBar(Message);

            string sLogFormat = DateTime.Now.ToShortDateString().ToString() + " " + DateTime.Now.ToLongTimeString().ToString() + " ==&gt; ";
            //string sPathName = @"E:\";
            string sPathName = @"SMSapplicationErrorLog_";

            string sYear = DateTime.Now.Year.ToString();
            string sMonth = DateTime.Now.Month.ToString();
            string sDay = DateTime.Now.Day.ToString();

            string sErrorTime = sDay + "-" + sMonth + "-" + sYear;

            sw = new StreamWriter(sPathName + sErrorTime + ".txt", true);

            sw.WriteLine(sLogFormat + Message);
            sw.Flush();

        }
        catch (Exception ex)
        {
            ErrorLog(ex.ToString());
        }
        finally
        {
            if (sw != null)
            {
                sw.Dispose();
                sw.Close();
            }
        }

    }
    #endregion 

    private void sendsms_Click(object sender, EventArgs e)
    {
        try
        {

            if (objclsSMS.sendMsg(this.port, this.sim.Text, this.mssging.Text))
            {
                //MessageBox.Show("Message has sent successfully");
                this.statusBar1.Text = "Message has sent successfully";
            }
            else
            {
                //MessageBox.Show("Failed to send message");
                this.statusBar1.Text = "Failed to send message";
            }

        }
        catch (Exception ex)
        {
            ErrorLog(ex.Message);
        }
    }


}
}
</code></pre>

<p>This is the class for Sending SMS</p>

<pre><code>using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO.Ports;
using System.Threading;
using System.Text.RegularExpressions;

namespace Queue.Classes
{
 public class clsSMS
 {
    #region Open and Close Ports
    //Open Port
    public SerialPort OpenPort(string p_strPortName, int p_uBaudRate, int p_uDataBits, int p_uReadTimeout, int p_uWriteTimeout)
    {
        receiveNow = new AutoResetEvent(false);
        SerialPort port = new SerialPort();

        try
        {
            port.PortName = p_strPortName;                 //COM1
            port.BaudRate = p_uBaudRate;                   //9600
            port.DataBits = p_uDataBits;                   //8
            port.StopBits = StopBits.One;                  //1
            port.Parity = Parity.None;                     //None
            port.ReadTimeout = p_uReadTimeout;             //300
            port.WriteTimeout = p_uWriteTimeout;           //300
            port.Encoding = Encoding.GetEncoding("iso-8859-1");
            port.DataReceived += new SerialDataReceivedEventHandler(port_DataReceived);
            port.Open();
            port.DtrEnable = true;
            port.RtsEnable = true;
        }
        catch (Exception ex)
        {
            throw ex;
        }
        return port;
    }

    //Close Port
    public void ClosePort(SerialPort port)
    {
        try
        {
            port.Close();
            port.DataReceived -= new SerialDataReceivedEventHandler(port_DataReceived);
            port = null;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    #endregion

    //Execute AT Command
    public string ExecCommand(SerialPort port, string command, int responseTimeout, string errorMessage)
    {
        try
        {

            port.DiscardOutBuffer();
            port.DiscardInBuffer();
            receiveNow.Reset();
            port.Write(command + "\r");

            string input = ReadResponse(port, responseTimeout);
            if ((input.Length == 0) || ((!input.EndsWith("\r\n&gt; ")) &amp;&amp; (!input.EndsWith("\r\nOK\r\n"))))
                throw new ApplicationException("No success message was received.");
            return input;
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    //Receive data from port
    public void port_DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        try
        {
            if (e.EventType == SerialData.Chars)
            {
                receiveNow.Set();
            }
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }
    public string ReadResponse(SerialPort port, int timeout)
    {
        string buffer = string.Empty;
        try
        {
            do
            {
                if (receiveNow.WaitOne(timeout, false))
                {
                    string t = port.ReadExisting();
                    buffer += t;
                }
                else
                {
                    if (buffer.Length &gt; 0)
                        throw new ApplicationException("Response received is incomplete.");
                    else
                        throw new ApplicationException("No data received from phone.");
                }
            }
            while (!buffer.EndsWith("\r\nOK\r\n") &amp;&amp; !buffer.EndsWith("\r\n&gt; ") &amp;&amp; !buffer.EndsWith("\r\nERROR\r\n"));
        }
        catch (Exception ex)
        {
            throw ex;
        }
        return buffer;
    }

    #region Count SMS
    public int CountSMSmessages(SerialPort port)
    {
        int CountTotalMessages = 0;
        try
        {

            #region Execute Command

            string recievedData = ExecCommand(port, "AT", 300, "No phone connected at ");
            recievedData = ExecCommand(port, "AT+CMGF=1", 300, "Failed to set message format.");
            String command = "AT+CPMS?";
            recievedData = ExecCommand(port, command, 1000, "Failed to count SMS message");
            int uReceivedDataLength = recievedData.Length;

            #endregion

            #region If command is executed successfully
            if ((recievedData.Length &gt;= 45) &amp;&amp; (recievedData.StartsWith("AT+CPMS?")))
            {

                #region Parsing SMS
                string[] strSplit = recievedData.Split(',');
                string strMessageStorageArea1 = strSplit[0];     //SM
                string strMessageExist1 = strSplit[1];           //Msgs exist in SM
                #endregion

                #region Count Total Number of SMS In SIM
                CountTotalMessages = Convert.ToInt32(strMessageExist1);
                #endregion

            }
            #endregion

            #region If command is not executed successfully
            else if (recievedData.Contains("ERROR"))
            {

                #region Error in Counting total number of SMS
                string recievedError = recievedData;
                recievedError = recievedError.Trim();
                recievedData = "Following error occured while counting the message" + recievedError;
                #endregion

            }
            #endregion

            return CountTotalMessages;

        }
        catch (Exception ex)
        {
            throw ex;
        }

    }
    #endregion

    #region Read SMS

    public AutoResetEvent receiveNow;

    public ShortMessageCollection ReadSMS(SerialPort port, string p_strCommand)
    {

        // Set up the phone and read the messages
        ShortMessageCollection messages = null;
        try
        {

            #region Execute Command
            // Check connection
            ExecCommand(port, "AT", 300, "No phone connected");
            // Use message format "Text mode"
            ExecCommand(port, "AT+CMGF=1", 300, "Failed to set message format.");
            // Use character set "PCCP437"
            ExecCommand(port, "AT+CSCS=\"PCCP437\"", 300, "Failed to set character set.");
            // Select SIM storage
            ExecCommand(port, "AT+CPMS=\"SM\"", 300, "Failed to select message storage.");
            // Read the messages
            string input = ExecCommand(port, p_strCommand, 5000, "Failed to read the messages.");
            #endregion

            #region Parse messages
            messages = ParseMessages(input);
            #endregion

        }
        catch (Exception ex)
        {
            throw ex;
        }

        if (messages != null)
            return messages;
        else
            return null;

    }
    public ShortMessageCollection ParseMessages(string input)
    {
        ShortMessageCollection messages = new ShortMessageCollection();
        try
        {
            Regex r = new Regex(@"\+CMGL: (\d+),""(.+)"",""(.+)"",(.*),""(.+)""\r\n(.+)\r\n");
            Match m = r.Match(input);
            while (m.Success)
            {
                ShortMessage msg = new ShortMessage();
                //msg.Index = int.Parse(m.Groups[1].Value);
                msg.Index = m.Groups[1].Value;
                msg.Status = m.Groups[2].Value;
                msg.Sender = m.Groups[3].Value;
                msg.Alphabet = m.Groups[4].Value;
                msg.Sent = m.Groups[5].Value;
                msg.Message = m.Groups[6].Value;
                messages.Add(msg);

                m = m.NextMatch();
            }

        }
        catch (Exception ex)
        {
            throw ex;
        }
        return messages;
    }

    #endregion

    #region Send SMS

    static AutoResetEvent readNow = new AutoResetEvent(false);

    public bool sendMsg(SerialPort port, string PhoneNo, string Message)
    {
        bool isSend = false;

        try
        {

            string recievedData = ExecCommand(port, "AT", 300, "No phone connected");
            recievedData = ExecCommand(port, "AT+CMGF=1", 300, "Failed to set message format.");
            String command = "AT+CMGS=\"" + PhoneNo + "\"";
            recievedData = ExecCommand(port, command, 300, "Failed to accept phoneNo");
            command = Message + char.ConvertFromUtf32(26) + "\r";
            recievedData = ExecCommand(port, command, 3000, "Failed to send message"); //3 seconds
            if (recievedData.EndsWith("\r\nOK\r\n"))
            {
                isSend = true;
            }
            else if (recievedData.Contains("ERROR"))
            {
                isSend = false;
            }
            return isSend;
        }
        catch (Exception ex)
        {
            throw ex;
        }

    }
    static void DataReceived(object sender, SerialDataReceivedEventArgs e)
    {
        try
        {
            if (e.EventType == SerialData.Chars)
                readNow.Set();
        }
        catch (Exception ex)
        {
            throw ex;
        }
    }

    #endregion



  }
 }
</code></pre>

<p>This is the another class for get and set:</p>

<pre><code>using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.IO.Ports;
using System.Threading;
using System.Text.RegularExpressions;

namespace Queue.Classes
{
public class ShortMessage
{
    #region Private Variables
    private string index;
    private string status;
    private string sender;
    private string alphabet;
    private string sent;
    private string message;
    #endregion

    #region Public Properties
    public string Index
    {
        get { return index; }
        set { index = value; }
    }
    public string Status
    {
        get { return status; }
        set { status = value; }
    }
    public string Sender
    {
        get { return sender; }
        set { sender = value; }
    }
    public string Alphabet
    {
        get { return alphabet; }
        set { alphabet = value; }
    }
    public string Sent
    {
        get { return sent; }
        set { sent = value; }
    }
    public string Message
    {
        get { return message; }
        set { message = value; }
    }
    #endregion

}

public class ShortMessageCollection : List&lt;ShortMessage&gt;
{
}
}
</code></pre>
