Question

I have the following simplified classes:

public class BaseContainer
{
    public BaseContainer()
    {
        Children = new ObservableCollection<BaseContainer>();
    }
    public ObservableCollection<BaseContainer> Children { get; set; }
}

public class ItemA : BaseContainer
{
    public ItemA()
    {
        base.Children.Add(new ItemB() { ItemBName = "bb" });
        base.Children.Add(new ItemA() { ItemAName = "ab" });
        base.Children.Add(new ItemB() { ItemBName = "ba" });
        base.Children.Add(new ItemA() { ItemAName = "aa" });
    }
    public string ItemAName { get; set; }
}

public class ItemB : BaseContainer
{
    public string ItemBName { get; set; }
}

I’m trying to sort my ItemA.Children collection based on two conditions:

1. All Item A’s must come first in the collection
2. Item A’s should be sorted by ItemAName
3. Item B’s should be sorted by ItemBName

So after sorting I’d expect something like this:

• ItemA – ItemAName = “aa”
• ItemA – ItemAName = “ab”
• ItemB – ItemBName = “ba”
• ItemB – ItemBName = “bb”

Any ideas on how to accomplish this?

I was able to sort by class type name:

        List<BaseContainer> temp = base.Children.ToList();
        temp.Sort((x, y) => string.Compare(x.GetType().Name, y.GetType().Name));
        base.Children.Clear();
        base.Children.AddRange(temp);

But Names are not sorted…

Thanks!

Answer 1

This will get all the A’s, order them by AName, then concat with all the B’s ordered by B name.

var result = Children.OfType<ItemA>().OrderBy(a => a.ItemAName).Cast<Base>()
    .Concat(Children.OfType<ItemB>().OrderBy(b => b.ItemBName));

I’m not sure this is the design I would go with… you might consider adding something to the base class to facilitate this kind of sorting.