Private Shared Function StrPtr(ByVal o As Object) As Integer
        Dim GC As System.Runtime.InteropServices.GCHandle = _
          System.Runtime.InteropServices.GCHandle.Alloc(o, _
          System.Runtime.InteropServices.GCHandleType.Pinned)
        Dim ret As Integer = GC.AddrOfPinnedObject.ToInt32
        GC.Free()
        Return ret
    End Function