GroupByCount

GroupingExtensions.cs

// http://devlicio.us/blogs/derik_whittaker/archive/2012/10/20/how-to-split-a-list-into-chunks-fun-code.aspx

static class GroupingExtensions
{
    public static IEnumerable<IEnumerable<T>> GroupByCount<T>(this IEnumerable<T> source, int count)
    {
        if (source == null) throw new ArgumentNullException("source");
        return GroupByCountIterator<T>(source, count);
    }

    static IEnumerable<IEnumerable<T>> GroupByCountIterator<T> (IEnumerable<T> source, int count)
    {
        using (IEnumerator<T> e = source.GetEnumerator())
        {
            while (e.MoveNext())
            {
                yield return TakeIterator<T>(e, count);
            }
        }
    }

    static IEnumerable<T> TakeIterator<T>(IEnumerator<T> e, int count)
    {
        if (count <= 0)
            return;
        do
        {
            yield return e.Current;
        } while (--count > 0 && e.MoveNext());
    }
}