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copied!<p>May I suggest something that doesn't involve creating strings, copying arrays or unsafe code:</p> <pre><code>using System; using System.Collections.Generic; static class ByteArrayRocks { static readonly int [] Empty = new int [0]; public static int [] Locate (this byte [] self, byte [] candidate) { if (IsEmptyLocate (self, candidate)) return Empty; var list = new List<int> (); for (int i = 0; i < self.Length; i++) { if (!IsMatch (self, i, candidate)) continue; list.Add (i); } return list.Count == 0 ? Empty : list.ToArray (); } static bool IsMatch (byte [] array, int position, byte [] candidate) { if (candidate.Length > (array.Length - position)) return false; for (int i = 0; i < candidate.Length; i++) if (array [position + i] != candidate [i]) return false; return true; } static bool IsEmptyLocate (byte [] array, byte [] candidate) { return array == null || candidate == null || array.Length == 0 || candidate.Length == 0 || candidate.Length > array.Length; } static void Main () { var data = new byte [] { 23, 36, 43, 76, 125, 56, 34, 234, 12, 3, 5, 76, 8, 0, 6, 125, 234, 56, 211, 122, 22, 4, 7, 89, 76, 64, 12, 3, 5, 76, 8, 0, 6, 125 }; var pattern = new byte [] { 12, 3, 5, 76, 8, 0, 6, 125 }; foreach (var position in data.Locate (pattern)) Console.WriteLine (position); } } </code></pre> <hr> <p><strong>Edit (by IAbstract)</strong> - <em>moving contents of <a href="https://stackoverflow.com/a/283815/210709">post</a> here since it is not an answer</em></p> <p>Out of curiosity, I've created a small benchmark with the different answers.</p> <p>Here are the results for a million iterations:</p> <pre><code>solution [Locate]: 00:00:00.7714027 solution [FindAll]: 00:00:03.5404399 solution [SearchBytePattern]: 00:00:01.1105190 solution [MatchBytePattern]: 00:00:03.0658212 </code></pre> <hr>

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