TextBox'ta girilen girdinin e-mailime gelmesi

MailMessage mail = new MailMessage("gonderen@mailadresi.com", "alan@mailadresi.com"); 
  SmtpClient client = new SmtpClient(); 
  client.Port = 25; 
  client.DeliveryMethod = SmtpDeliveryMethod.Network; 
  client.UseDefaultCredentials = false; 
  client.Host = "smtp.google.com"; 
  mail.Subject = "this is a test email."; 
  mail.Body = "this is my test email body"; 
  client.Send(mail);