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copied!<p><code>List<T></code> has a built-in function called <code>GetRange()</code> which was made specifically for what you're trying to do. It's extremely fast and doesn't need Linq, casting, etc...</p> <pre><code>List<string> prodASINs = dc.aboProducts.Select(a => a.asin).ToList(); for(int i = 0; i < prodASINs.Count; i += 10) { List<string> buffer = prodASINs.GetRange(i, 10); // do something with buffer } </code></pre> <p>That's it. Very simple.</p> <hr> <p>Test results: <code>GetRange</code> vs. <code>Slice</code> vs. <code>Linq</code> with 5000 strings in <code>List<string></code> As you can clearly see, the Skip/Take approach using Linq is over 383 times slower than <code>Slice<T>()</code> and 4,736 times slower than <code>GetRange()</code></p> <p>==================================================================================</p> <pre><code>GetRange took on average 168 ticks Slice took on average 2073 ticks Linq took on average 795643 ticks </code></pre> <p>Test method used (try it yourself): </p> <pre><code>private static void GetRangeVsSliceVsLinq() { List<string> stringList = new List<string>(); for (int i = 0; i < 5000; i++) { stringList.Add("This is a test string " + i.ToString()); } Stopwatch sw = new Stopwatch(); long m1 = 0, m2 = 0, m3 = 0; for (int x = 0; x < 10; x++) { Console.WriteLine("Iteration {0}", x + 1); Console.WriteLine(); sw.Reset(); sw.Start(); for (int i = 0; i < stringList.Count; i += 10) { List<string> buffer = stringList.GetRange(i, 10); } sw.Stop(); Console.WriteLine("GetRange took {0} msecs", sw.ElapsedMilliseconds); Console.WriteLine("GetRange took {0} ticks", sw.ElapsedTicks); m1 += sw.ElapsedTicks; sw.Reset(); sw.Start(); string[] sliceArray = stringList.ToArray(); for (int i = 0; i < sliceArray.Length; i += 10) { List<string> buffer = sliceArray.Slice(i, 10).ToList(); } sw.Stop(); Console.WriteLine("Slice took {0} msecs", sw.ElapsedMilliseconds); Console.WriteLine("Slice took {0} ticks", sw.ElapsedTicks); m2 += sw.ElapsedTicks; sw.Reset(); sw.Start(); var count = stringList.Count(); for (var i = 0; i < count; i++) { var buffer = stringList.Skip(i * 10).Take(10).ToList(); } sw.Stop(); Console.WriteLine("Skip/Take took {0} msecs", sw.ElapsedMilliseconds); Console.WriteLine("Skip/Take took {0} ticks", sw.ElapsedTicks); m3 += sw.ElapsedTicks; Console.WriteLine(); } Console.WriteLine(); Console.WriteLine("GetRange took on average {0} ticks", m1 / 10); Console.WriteLine("Slice took on average {0} ticks", m2 / 10); Console.WriteLine("Linq took on average {0} ticks", m3 / 10); } </code></pre>

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