C#

using System.Runtime.InteropServices;
...
public static object ByteArrayToStructure(byte[] buffer, int index, Type tStructure)
{
    if (null == buffer || 0 == buffer.Length)
        throw new ArgumentNullException("buffer");
    if (0 > index || buffer.Length <= index)
        throw new ArgumentOutOfRangeException("index");
    if (null == tStructure)
        throw new ArgumentNullException("tStructure");
    
    int size = Marshal.SizeOf(tStructure);
    if (index + buffer.Length < size)
        throw new ArgumentException("Insufficient data passed", "buffer");
    
    IntPtr pStructure = Marshal.AllocHGlobal(size);
    try
    {
        Marshal.Copy(buffer, index, pStructure, size);
        return Marshal.PtrToStructure(pStructure, tStructure);
    }
    finally
    {
        Marshal.FreeHGlobal(pStructure);
    }
}

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<br />
 [<br />
        StructLayout(LayoutKind.Sequential)<br />
    ]<br />
 public struct _GUID<br />
 {<br />
  public uint x;<br />
  public ushort s1;<br />
  public ushort s2;<br />
<br />
  [MarshalAs(UnmanagedType.ByValArray, SizeConst=8)]<br />
  public byte[] c;<br />
 }<br />
<br />
 [<br />
 StructLayout(LayoutKind.Sequential)<br />
 ]<br />
 public struct _FILETIME<br />
 {<br />
  public uint dwLowDateTime;<br />
  public uint dwHighDateTime;<br />
 }<br />
<br />
 [<br />
 StructLayout(LayoutKind.Sequential)<br />
 ]<br />
 public struct tagSTATSTG<br />
 {<br />
  [MarshalAs(UnmanagedType.LPWStr)]<br />
  public string pwcsName;<br />
  public uint type;<br />
  public _ULARGE_INTEGER cbSize;<br />
  public _FILETIME mtime;<br />
  public _FILETIME ctime;<br />
  public _FILETIME atime;<br />
  public uint grfMode;<br />
  public uint grfLocksSupported;<br />
  public _GUID clsid;<br />
  public uint grfStateBits;<br />
  public uint reserved;<br />
 }<br />
<br />
 [<br />
 InterfaceType(ComInterfaceType.InterfaceIsIUnknown),<br />
 Guid("0c733a30-2a1c-11ce-ade5-00aa0044773d")<br />
 ]<br />
 public interface ISequentialStream<br />
 {<br />
  void Read(out byte pv, uint cb, out uint pcbRead);<br />
<br />
  void Write(out byte pv, uint cb, out uint pcbWritten);<br />
 }<br />
<br />
 [<br />
 InterfaceType(ComInterfaceType.InterfaceIsIUnknown),<br />
 Guid("0000000C-0000-0000-C000-000000000046")<br />
 ]<br />
 public interface IStream : ISequentialStream<br />
 {<br />
  void Seek(_LARGE_INTEGER dlibMove, uint dwOrigin, out _ULARGE_INTEGER<br />
plibNewPosition);<br />
<br />
  void SetSize(_ULARGE_INTEGER libNewSize);<br />
<br />
  void CopyTo(IStream pstm, _ULARGE_INTEGER cb, out _ULARGE_INTEGER pcbRead,<br />
out _ULARGE_INTEGER pcbWritten);<br />
<br />
  void Commit(uint grfCommitFlags);<br />
<br />
  void Revert();<br />
<br />
  void LockRegion(_ULARGE_INTEGER libOffset, _ULARGE_INTEGER cb, uint<br />
dwLockType);<br />
<br />
  void UnlockRegion(_ULARGE_INTEGER libOffset, _ULARGE_INTEGER cb, uint<br />
dwLockType);<br />
<br />
  void Stat(out tagSTATSTG pstatstg, uint grfStatFlag);<br />
<br />
  void Clone(out IStream ppstm);<br />
 }<br />
<br />
 [<br />
 InterfaceType(ComInterfaceType.InterfaceIsIUnknown),<br />
 Guid("0000010C-0000-0000-C000-000000000046")<br />
 ]<br />
 public interface IPersist<br />
 {<br />
  void GetClassID(out _GUID a);<br />
 }<br />
<br />
 [<br />
 StructLayout(LayoutKind.Sequential)<br />
 ]<br />
 public struct _ULARGE_INTEGER<br />
 {<br />
  public ulong QuadPart;<br />
 }<br />
<br />
 [<br />
 StructLayout(LayoutKind.Sequential)<br />
 ]<br />
 public struct _LARGE_INTEGER<br />
 {<br />
  public long QuadPart;<br />
 }<br />
<br />
 [<br />
 InterfaceType(ComInterfaceType.InterfaceIsIUnknown),<br />
 Guid("00000109-0000-0000-C000-000000000046")<br />
 ]<br />
 public interface IPersistStream : IPersist<br />
 {<br />
  [PreserveSig()]<br />
  int IsDirty();<br />
<br />
  void Load(IStream Stm);<br />
<br />
  void Save(IStream Stm, int ClearDirty);<br />
<br />
  void GetSizeMax(out _ULARGE_INTEGER Size);<br />
 }<br />
<br />
 [<br />
 ProgId("ICRMMC.IcrSnapin"),<br />
 Guid("43C8177A-2392-419F-9156-34D24FE22319"),<br />
 ClassInterface(ClassInterfaceType.None)<br />
 ]<br />
 public class IcrSnapin : IPersistStream<br />
 {<br />
  public IcrSnapin()<br />
  {<br />
  }<br />
<br />
  public void GetClassID(out _GUID a)<br />
  {<br />
   a.x = 0x43C8177A;<br />
   a.s1 = 0x2392;<br />
   a.s2 = 0x419F;<br />
   a.c = new Byte [] {0x91, 0x56, 0x34, 0xD2, 0x4F, 0xE2, 0x23, 0x19};<br />
  }<br />
<br />
  public int IsDirty()<br />
  {<br />
   return 1;<br />
  }<br />
<br />
  public void Load(IStream Stm)<br />
  {<br />
  }<br />
<br />
  public void Save(IStream Stm, int ClearDirty)<br />
  {<br />
  }<br />
<br />
  public void GetSizeMax(out _ULARGE_INTEGER Size)<br />
  {<br />
   Size.QuadPart = 1234;<br />
  }<br />
<br />
 }<br />