windows programming

Hi,

Below is the code that takes email ids from an Excel file and send emails to all the email ids with textBox1 text as message body. It uses a Gmail account to send emails. You can use other email account with their corresponding smtp client and other details.

Add reference to "Microsoft.Office.Interop.Excel"  using Add Reference dialog box.

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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.Net;
using System.Net.Mail;
using System.Data.OleDb;
using Excel = Microsoft.Office.Interop.Excel;

namespace Email
{
    public partial class eMail : Form
    {
        String Email;        
        String SheetName = "Sheet1";    // Name of the sheet in the Excel file
        String ConString;
        MailMessage message;
        OleDbConnection con;
        OleDbCommand cmd;
        OleDbDataReader reader;
        SmtpClient smtp;

        public eMail()
        {
            InitializeComponent();

            // Email.xls file is stored in the Debug folder. Emails are stored in Sheet1 under heading Email            
            ConString = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=Email.xls;Extended Properties=Excel 8.0";
        }

        private void button1_Click(object sender, EventArgs e)
        {
            message = new MailMessage();
            con = new OleDbConnection(ConString);
            con.Open();
            cmd = new OleDbCommand(" SELECT Email FROM [" + SheetName + "$]", con);
            reader = cmd.ExecuteReader();           

            while (reader.Read())
            {
                Email= reader[0].ToString();
                message.To.Add(Email.Trim());
            }
            reader.Close();
            con.Close();
                        
            message.Subject = "Bulk Email using C#.net";
            message.From = new MailAddress("fromemailaddress");    //[email protected]
            message.Body = textBox1.Text;
            smtp = new SmtpClient("smtp.gmail.com");
            smtp.Port = 25;
            smtp.EnableSsl = true;
            smtp.Credentials = new NetworkCredential("("fromemailaddress");", "password");
            smtp.Send(message);
        }
    }
}

You can use the same mailing code in c# with to addresses separated by comma:

SmtpClient smtpClient = new SmtpClient("yourmailserver.com", 25);
smtpClient.UseDefaultCredentials = true;

MailMessage message = new MailMessage();
MailAddress fromAddress = new MailAddress("[email protected]", "Your Display Name");

message.To.Add("[email protected],[email protected],[email protected]"); // Add multiple mail addresses here

message.From = fromAddress;
message.Subject = "Your Subject";
message.Body = "The Message Body";
smtpClient.Send(message);