Web Forms :: How To Send Mail To Many Persons

i want to send mail to so many persons i used this code

MailMessage
mail.From = txt_from.Text.Trim();
mail.To = txt_to.Text.Trim();
mail.Cc = txt_cc.Text.Trim();
mail.Bcc = txt_bcc.Text.Trim();
mail.Subject = txt_subj.Text;
mail.Body = ftb_body.Text;
mail.BodyFormat =
mail = new
MailMessage();if (txt_cc.Text.Trim().Length != 0)if
(txt_bcc.Text.Trim().Length != 0)MailFormat.Html;SmtpMail.SmtpServer
= "localhost";
//your real server goes here
SmtpMail.Send(mail);

now i wnat to send so may perons

but i will give all mail id in to address only, i will send one by one.