how to write code for send email and forget password

//sending Email.
System.Net.Mail.MailMessage msg = new System.Net.Mail.MailMessage();
                msg.To.Add(TextBox1.Text);//Read user email id here
                msg.Subject = "Forgot password.";
                msg.From = new System.Net.Mail.MailAddress("autoemail@xyz.com");
                string passwrd="  "; //retrieve the password from database and assign it to password string.
                msg.Body += "Your user ID is " + TextBox1.Text+" and password is +"passwrd;
                msg.Body += "Have a great day!\n";
                msg.Body += "  \n  ";
                msg.Body += "-Team\n XYZ services!";

                System.Net.Mail.SmtpClient smtp = new System.Net.Mail.SmtpClient("localhost");//replace the localhost with hosting server name.For example in case of godaddy it is "relay-hosting.secureserver.net"
                smtp.Send(msg);