Right - the VB.Net spooler watch component is about 70% done but I am totally stuck on getting the DEVMODE structure as held in the pointer in JOB_INFO_2.

I keep getting the error:
An unhandled exception of type 'System.TypeLoadException' occurred in mscorlib.dll

Additional information:
Can not marshal field DeviceMode of type PrinterQueueWatch.JOB_INFO_2:
The type definition of this field has no layout information.
I have the DEVMODE structure defined as a class thus:
VB Code:
  1. <StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Ansi)> _

  2. Friend Class DEVMODE

  3.     <VBFixedString(32), MarshalAs(UnmanagedType.ByValTStr, SizeConst:=32)> Public pDeviceName As String  'CCHDEVICENAME

  4.     Public dmSpecversion As Int16

  5.     Public dmSize As Int16

  6.     Public dmDriverExtra As Int16

  7.     Public dmFields As Int32

  8.     <MarshalAs(UnmanagedType.U2)> Public dmOrientation As PrintJob.DeviceOrientations

  9.     <MarshalAs(UnmanagedType.U2)> Public dmPaperSize As PrintJob.PrinterPaperSizes

  10.     Public dmPaperLength As Int16

  11.     Public dmPaperWidth As Int16

  12.     Public dmScale As Int16

  13.     Public dmCopies As Int16

  14.     Public dmDefaultSource As Int16

  15.     Public dmPrintQuality As Int16

  16.     <MarshalAs(UnmanagedType.U2)> Public dmColor As PrintJob.DeviceColourModes

  17.     <MarshalAs(UnmanagedType.U2)> Public dmDuplex As PrintJob.DeviceDuplexSettings

  18.     Public dmYResolution As Int16

  19.     Public dmTTOption As Int16

  20.     Public dmCollate As Int16

  21.     <VBFixedString(32), MarshalAs(UnmanagedType.ByValTStr, SizeConst:=32)> Public dmFormName As String

  22.     Public dmUnusedPadding As Int16

  23.     Public dmBitsPerPel As Int16

  24.     Public dmPelsWidth As Int32

  25.     Public dmPelsHeight As Int32

  26.     Public dmDisplayFlags As Int32

  27.     Public dmDisplayFrequency As Int32

  28.  
  29. End Class

and the JOB_INFO_2 defined thus:-
VB Code:
  1. <StructLayout(LayoutKind.Sequential, CharSet:=CharSet.Ansi)> _

  2. Friend Class JOB_INFO_2

  3.     Public JobId As Int32

  4.     <MarshalAs(UnmanagedType.LPStr)> Public pPrinterName As String

  5.     <MarshalAs(UnmanagedType.LPStr)> Public pMachineName As String

  6.     <MarshalAs(UnmanagedType.LPStr)> Public pUserName As String

  7.     <MarshalAs(UnmanagedType.LPStr)> Public pDocument As String

  8.     <MarshalAs(UnmanagedType.LPStr)> Public pNotifyName As String

  9.     <MarshalAs(UnmanagedType.LPStr)> Public pDatatype As String

  10.     <MarshalAs(UnmanagedType.LPStr)> Public pPrintProcessor As String

  11.     <MarshalAs(UnmanagedType.LPStr)> Public pParameters As String

  12.     <MarshalAs(UnmanagedType.LPStr)> Public pDriverName As String

  13.     <MarshalAs(UnmanagedType.LPStruct)> Public DeviceMode As DEVMODE

  14.     <MarshalAs(UnmanagedType.LPStr)> Public pStatus As String

  15.     <MarshalAs(UnmanagedType.U4)> Public Status As PrintJob.Print_Job_Statuses

  16.     Public Priority As Int32

  17.     Public Position As Int32

  18.     Public TotalPage As Int32

  19.     Public PagesPrinted As Int32

  20.     <MarshalAs(UnmanagedType.Struct)> Public Submitted As SystemTime

  21. End Class

Any ideas what I have wrong here? I'm pretty sure the problem is in the DEVMODE class because if I return lpDevMode as an Int32, cast it to an IntPtr and use
VB Code:
  1. Marshal.PtrToStructue(lpDevModePtr, dmThis)
I get the same error.

Thanks in advance,
Duncan