/// <summary>
/// Remove attachment of mail to a mail group.
/// </summary>
/// <param name="id">Id of associate entry describing attachment.</param>
/// <returns>Removed attachment.</returns>
public MailGroupMail DeleteMailFromMailGroup(int id)
{
var mailGroupMail = _context.MailGroupMails
.Include(x => x.Mail)
.Include(x => x.MailGroup)
.SingleOrDefault(x => x.Id == id);
if (mailGroupMail == null)
{
return(null);
}
if (!isRequestValid(mailGroupMail.Mail, mailGroupMail.MailGroup))
{
return(null);
}
_context.Remove(mailGroupMail);
_context.SaveChanges();
return(mailGroupMail);
}
