您无需编写任何代码。使用MoreLINQ
Batch方法，它将源序列分批处理成大小的存储桶（MoreLINQ可作为NuGet包提供，您可以安装）：

int size = 10;
var batches = sequence.Batch(size);

实现为：

public static IEnumerable<IEnumerable<TSource>> Batch<TSource>(
                  this IEnumerable<TSource> source, int size)
{
    TSource[] bucket = null;
    var count = 0;

    foreach (var item in source)
    {
        if (bucket == null)
            bucket = new TSource[size];

        bucket[count++] = item;
        if (count != size)
            continue;

        yield return bucket;

        bucket = null;
        count = 0;
    }

    if (bucket != null && count > 0)
        yield return bucket.Take(count).ToArray();
}