EF4 LINQ Ordering Parent and all child collections with Eager Loading (.Include())

Question

I am doing hierarchical data binding on a grid, and I need to have the database server perform the sorting on my objects. I can easily sort the parent collection, but I can

Answer 1

If you need to have Ordering or Filtering on inner navigation properties (e.g. Models) then you cannot eager load them using Include method anymore. Instead, you can use EntityCollection<TEntity>.CreateSourceQuery Method like this:

List years = db.Years.OrderBy("it.Name").ToList();
foreach(year in years) 
{
    var makesQuery = year.Makes.CreateSourceQuery().OrderBy(m => m.Name);
    year.Makes.Attach(makesQuery);  

    foreach(make in year.Makes) 
    {
        var modelsQuery = make.Models.CreateSourceQuery().OrderBy(m => m.Name);
        make.Models.Attach(modelsQuery);

        foreach(model in make.Models) 
        {
            var colQuery = model.Colors.CreateSourceQuery().OrderBy(c => c.Name);
            model.Models.Attach(colQuery);        
        }
    }
}

This way, the years object will be constructed with having all of its navigation properties ordered.