public void btnRegister_Click(object sender, EventArgs e)
{
HEWDataContext context = new HEWDataContext();
if (context.Newsletters.Any(i => i.Email == txtMail.Text.Trim()))
{
return;
}
Newsletter newsletter = new Newsletter{Email = txtMail.Text.Trim()};
context.Newsletters.InsertOnSubmit(newsletter);
context.SubmitChanges();
txtMail.Text = string.Empty;
}
partial void UpdateNewsletter(Newsletter instance);
partial void DeleteNewsletter(Newsletter instance);
partial void InsertNewsletter(Newsletter instance);