using System;

using System.Linq;

using System.Collections.Generic;

​

public class Program

{

    public static void Main()

    {

        var emptyData = Enumerable.Empty<int>();

        var data = Enumerable.Range(1, 100);

        Console.WriteLine($"{nameof(emptyData)}:");

        Console.WriteLine(FormatResults(emptyData, 2));

        Console.WriteLine($"{nameof(data)}:");

        Console.WriteLine(FormatResults(data, 13));

    }

    private static string FormatResults<T>(IEnumerable<T> data, int partitionSize)

    {

        return string.Join($",{Environment.NewLine}", data.Partition(partitionSize).Select(i => $"( {string.Join(", ", i)} )"));

    }

}

​

public static class Ext

{

    public static IEnumerable<IList<T>> Partition<T>(

        this IEnumerable<T> source,

        int size)

    {

        if (size < 2)

        {

            throw new ArgumentOutOfRangeException(

                nameof(size),

                size,

                "Must be greater or equal to 2.");  

        }

        T[] partition;

        int count;

        using (var e = source.GetEnumerator())

        {

            if (e.MoveNext())

            {

                partition = new T[size];

                partition[0] = e.Current;

                count = 1;

            }

            else

            {

                yield break;    

            }

            while(e.MoveNext())

            {

                partition[count] = e.Current;

                count++;

                if (count == size)

                {

                    yield return partition;

                    count = 0;

                    partition = new T[size];

                }

            }

        }

        if (count > 0)

        {

            Array.Resize(ref partition, count);

            yield return partition;

        }

    }

}