ListCollectionView CustomSort 2 conditions

Question

I have a ListCollectionView in my ViewModel which I bind it to a ListBox. Let's say I have a collection of strings, where I first want to sort them by string length, then by alphabetical order. How should I do it?

Currently I managde to sort it by length using CustomSort by implementing my own IComparer class, but how can I do it such that it is also in alphabetical order for the strings with the same length.

Answer 1

You can easily use LINQ to do that:

List<string> list = GetTheStringsFromSomewhere();
List<string> ordered = list.OrderBy(p => p.Length).ThenBy(p => p).ToList();

EDIT:

You mentioned CustomSort and SortDescription in your comment. I think (untested) you should be able to achieve the same result by rolling your own Comparer:

public class ByLengthAndAlphabeticallyOrderComparer : IComparer
{
    int IComparer.Compare(Object x, Object y)
    {
        var stringX = x as string;
        var stringY = y as string;

        int lengthDiff = stringX.Length - stringY.Length;           
        if (lengthDiff !=)
        {
            return lengthDiff < 0 ? -1 : 1; // maybe the other way around -> untested ;)
        }

        return stringX.Compare(stringY);
    }
}

Usage:

_yourListViewControl.CustomSort = new ByLengthAndAlphabeticallyOrderComparer();