public struct CIDA
/// Number of PIDLs that are being transferred, not counting the parent folder.
public uint cidl;
/// An array of offsets, relative to the beginning of this structure. The array contains
/// cidl+1 elements. The first element of aoffset contains an offset to the fully-qualified
/// PIDL of a parent foloder. If this PIDL is empty, the parent folder is the desktop.
/// Each of the remaining elements of the array contains an offset to one of the PIDLs to be
/// transferred. ALL of these PIDLs are relative to the PIDL of the parent folder.
[MarshalAs(UnmanagedType.ByValArray, SizeConst = 1)]
public uint aoffset;