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copied!<p><strong>You're better off using a library like <a href="http://morelinq.googlecode.com/" rel="noreferrer">MoreLinq</a>, but if you really had to do this using "plain LINQ", you can use <code>GroupBy</code>:</strong></p> <pre><code>var sequence = new[] {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16}; var result = sequence.Select((x, i) => new {Group = i/8, Value = x}) .GroupBy(item => item.Group, g => g.Value) .Select(g => g.Where(x => true)); // result is: { {1,2,3,4,5,6,7,8}, {9,10,11,12,13,14,15,16} } </code></pre> <p>Basically, we use the version of <code>Select()</code> that provides an index for the value being consumed, we divide the index by 8 to identify which group each value belongs to. Then we group the sequence by this grouping key. The last <code>Select</code> just reduces the <code>IGrouping<></code> down to an <code>IEnumerable<IEnumerable<T>></code> (and isn't strictly necessary since <code>IGrouping</code> is an <code>IEnumerable</code>).</p> <p>It's easy enough to turn this into a reusable method by factoring our the constant <code>8</code> in the example, and replacing it with a specified parameter. It's not necessarily the most elegant solution, and it is not longer a lazy, streaming solution ... but it does work.</p> <p>You could also write your own extension method using iterator blocks (<code>yield return</code>) which could give you better performance and use less memory than <code>GroupBy</code>. This is what the <code>Batch()</code> method of MoreLinq does IIRC.</p>

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