DOCINFOA    di = new DOCINFOA();

static extern int StartDoc(IntPtr hdc, [In] ref DOCINFO lpdi);

class DOCINFOW {

  Structure DOCINFOW

struct DOCINFOW {

  Structure DOCINFOW

  Public Function StartDocPrinter(hPrinter As IntPtr, Level As Integer, ByRef pDocInfo As DOC_INFO_1W) As Long

  Public Function StartDocPrinter(hPrinter As IntPtr, Level As Integer, ByRef pDocInfo As DOC_INFO_1A) As Long