Sending email to many in databes table

Question

The below program show me 

 

A recipient must be specified.

Kindly help 

 

 

public partial class _Default : System.Web.UI.Page

{

DataSet ds = new DataSet();

SqlCommand cmd = new SqlCommand();

protected void Page_Load(object sender, EventArgs e)

{

}

protected void btnSendEmail_Click(object sender, EventArgs e)

{

if (txtemailfrom.Text == "" || txtsubject.Text == "" || txtbody.Text == "")

{

lblmail.Text = "Please fill all mandatory fields.";

lblmail.Visible = true;

return;

}

SmtpClient smtpClient = new SmtpClient();

MailMessage mailMessage = new MailMessage();

SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["stringconnect"].ConnectionString);

ArrayList list_emails = new ArrayList();

int i = 0;

string email;

con.Open();

SqlCommand cmd = new SqlCommand("Select EmailId from SendEmailToStudent", con);

SqlDataReader read_Email = cmd.ExecuteReader();

while (read_Email.Read())

{

email = read_Email.GetValue(i).ToString();

list_emails.Add(email); //Add email to a arraylist

i = i + 1 - 1;

}

read_Email.Close();

con.Close(); //Close connection

foreach (string email_to in list_emails)

{

if (fileAttachement.PostedFile != null)

{

HttpPostedFile AttachFile = fileAttachement.PostedFile;

int AttachFileLength = AttachFile.ContentLength;

if (AttachFileLength > 0)

{

// FileName = Path.GetFileName(fileAttachement.PostedFile.FileName);

}

}

MailAddress fromAddress = new MailAddress(txtemailfrom.Text);

mailMessage.From = fromAddress;

mailMessage.Subject = txtsubject.Text;

mailMessage.Body = txtbody.Text;

string Body = "";

Body += '\n' + "From:" + txtemailfrom.Text;

Body += '\n' + "";

Body += '\n' + "Subject:" + txtsubject.Text;

Body += '\n' + "";

Body += '\n' + txtbody.Text;

mailMessage.IsBodyHtml = true;

mailMessage.Body = Body;

SmtpClient smtp = new SmtpClient("SMTP Server");

smtpClient.Send(mailMessage);

lblmail.Visible = true;

lblmail.Text = "Your mail has been sent successfully";

tblemail.Visible = true;

}

txtemailfrom.Text = "";

txtsubject.Text = "";

txtbody.Text = "";

}

}