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copied!<p>There is a way which avoids memory copying and iteration.</p> <p>You can use a really ugly hack to temporary change your array to another type using (unsafe) memory manipulation.</p> <p>I tested this hack in both 32 & 64 bit OS, so it should be portable.</p> <p>The source + sample usage is maintained at <a href="https://gist.github.com/1050703" rel="noreferrer">https://gist.github.com/1050703</a> , but for your convenience I'll paste it here as well:</p> <pre><code>public static unsafe class FastArraySerializer { [StructLayout(LayoutKind.Explicit)] private struct Union { [FieldOffset(0)] public byte[] bytes; [FieldOffset(0)] public float[] floats; } [StructLayout(LayoutKind.Sequential, Pack = 1)] private struct ArrayHeader { public UIntPtr type; public UIntPtr length; } private static readonly UIntPtr BYTE_ARRAY_TYPE; private static readonly UIntPtr FLOAT_ARRAY_TYPE; static FastArraySerializer() { fixed (void* pBytes = new byte[1]) fixed (void* pFloats = new float[1]) { BYTE_ARRAY_TYPE = getHeader(pBytes)->type; FLOAT_ARRAY_TYPE = getHeader(pFloats)->type; } } public static void AsByteArray(this float[] floats, Action<byte[]> action) { if (floats.handleNullOrEmptyArray(action)) return; var union = new Union {floats = floats}; union.floats.toByteArray(); try { action(union.bytes); } finally { union.bytes.toFloatArray(); } } public static void AsFloatArray(this byte[] bytes, Action<float[]> action) { if (bytes.handleNullOrEmptyArray(action)) return; var union = new Union {bytes = bytes}; union.bytes.toFloatArray(); try { action(union.floats); } finally { union.floats.toByteArray(); } } public static bool handleNullOrEmptyArray<TSrc,TDst>(this TSrc[] array, Action<TDst[]> action) { if (array == null) { action(null); return true; } if (array.Length == 0) { action(new TDst[0]); return true; } return false; } private static ArrayHeader* getHeader(void* pBytes) { return (ArrayHeader*)pBytes - 1; } private static void toFloatArray(this byte[] bytes) { fixed (void* pArray = bytes) { var pHeader = getHeader(pArray); pHeader->type = FLOAT_ARRAY_TYPE; pHeader->length = (UIntPtr)(bytes.Length / sizeof(float)); } } private static void toByteArray(this float[] floats) { fixed(void* pArray = floats) { var pHeader = getHeader(pArray); pHeader->type = BYTE_ARRAY_TYPE; pHeader->length = (UIntPtr)(floats.Length * sizeof(float)); } } } </code></pre> <p>And the usage is:</p> <pre><code>var floats = new float[] {0, 1, 0, 1}; floats.AsByteArray(bytes => { foreach (var b in bytes) { Console.WriteLine(b); } }); </code></pre>

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