using System;

using System.Collections.Generic;

using System.Linq;

using Newtonsoft.Json;

​

public class Program

{

​

    public static void Main()

    {

        var inputs = Enumerable.Range(0,10).ToArray();

        var count = 0;

        foreach(var batch in inputs.Batch(2))

            ++count;

        var temp1= inputs.Batch(2);

        var temp2= inputs.Batch(2).Count();

        var temp3= inputs.Batch(2).ToList();

        var temp4= inputs.Batch(2).ToList().Count();

        var temp5= temp3.Count();

        count.Dump();

        temp1.Dump();

        temp2.Dump();

        temp3.Dump();

        temp4.Dump();

        temp5.Dump();

    }

}

​

public static class ExtFoo{

        public static IEnumerable<IEnumerable<T>> Batch<T>(this IEnumerable<T> source, int size) {

        using (IEnumerator<T> enumerator = source.GetEnumerator())

            while (enumerator.MoveNext())

                yield return TakeIEnumerator(enumerator, size);

    }

​

    private static IEnumerable<T> TakeIEnumerator<T>(IEnumerator<T> source, int size) {

        int i = 0;

        do yield return source.Current;

        while (++i < size && source.MoveNext());

    }

}