BatchAggregate

gistfile1.cs

public static IEnumerable<IList<T>> BatchAggregate<T>(this IEnumerable<T> source, int batchSize)
{
    var list = new List<T>(batchSize);

    foreach(var item in source)
    {
        list.Add(item);
        if (list.Count == batchSize)
        {
            yield return list;
            list = new List<T>(batchSize);
        }
    }

    if (list.Any())
        yield return list;
}