How to sort an IEnumerable

Question

How can I sort an IEnumerable alphabetically. Is this possible?

Edit: How would I write an in-place solution?

Answer 1

We can't always do it in-place, but we detect when it's possible:

IEnumerable SortInPlaceIfCan(IEnumerable src, IComparer cmp)
{
  List listToSort = (src is List) ? (List)src : new List(src);
  listToSort.Sort(cmp);
  return listToSort;
}
IEnumerable SortInPlaceIfCan(IEnumerable src, Comparison cmp)
{
  return SortInPlaceIfCan(src, new FuncComparer(cmp));
}
IEnumerable SortInPlaceIfCan(IEnumerable src)
{
  return SortInPlaceIfCan(src, Comparer.Default);
}

This uses the following handy struct:

internal struct FuncComparer : IComparer
{
  private readonly Comparison _cmp;
  public FuncComparer(Comparison cmp)
  {
      _cmp = cmp;
  }
  public int Compare(T x, T y)
  {
      return _cmp(x, y);
  }
}