void checkIfParentRelated(Salesman child)
{
if (child.ParentSalesmanId.IsNullOrWhiteSpace())
{
return;
}
if (child.ParentSalesman.IsNull())
{
child.ParentSalesman = Find(child.ParentSalesmanId);
}
child.ParentSalesman.IsNullThrowException();
stackOfAncestors.Push(child);
if (isExpectedParentRelatedToChild(child.ParentSalesman, child))
{
string err = string.Format("'{0}' and '{1}' are already related. {2}", child.ParentSalesman.FullName(), child.FullName(), listAncestors());
throw new Exception(err);
}
}
