Hi

I'm trying to define the following C++ shell struct in C# (see shtypes.h or
shtypes.idl):

typedef struct _SHITEMID {
   USHORT cb;
   BYTE abID[1];
} SHITEMID;

where cb is the size of the whole struct (in bytes) including cb itself and
abID can have a variable length.

here is my definition (I fixed the abID size to 4 bytes - 2 bytes data and 2
bytes for a recommended terminator '\0'):

[StructLayout(LayoutKind.Sequential, Size=6)]
public struct SHITEMID
{
    public UInt16 cb; // 2 bytes
    public UInt16 abID; // 2 bytes
//   public UInt16 terminator; // 2 bytes
    public SHITEMID(short val)
    {
         if (val == 0)
             cb = 0;
        else
             cb=6;
       abID= val;
//      terminator = 0;
      }
}

This struct works fine together with the shell. But if I uncomment the two
out commented lines, windows explorer crashes. I have absolutely no idea why
this happens. As you can see, the struct has always a length of 6 bytes -
whether the lines are uncommented or not. And in both cases, the last 2
bytes are zero, right?

Any suggestions? It's driving me crazy. The terminator seems to be the key.

Thanx for your help in advance.
Thomas

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