Need help with LINQ Query - Order by bool, then parent -> children

[jmcilhinney]

So basically you're saying that a parent is listed after its children rather than before, correct? If so then try this:

model = _repository.GetAll()
                   .OrderByDescending(x => x.ParentService == null ? x.Compulsory : x.ParentService.Compulsory)
                   .ThenBy(x => x.ParentService == null ? x.Name : x.ParentName)
                   .ThenByDescending(x => x.ParentService == null)
                   .ThenBy(x => x.Name);

That is, again, untested.