public void Submit()
{
if (HasEnded)
{
throw new ObjectDisposedException("Unit of Work has been disposed.");
}
if (_context != null)
{
_rules.ApplyInsertRules(_context.Changes(EntityState.Added));
_rules.ApplyDeleteRules(_context.Changes(EntityState.Modified));
_rules.ApplyUpdateRules(_context.Changes(EntityState.Deleted));
_context.SaveChanges();
}
}