/// <summary>
/// Sends the specified raw string to the printer.
/// </summary>
/// <param name="printerName">
/// The name of the printer which receives the string.
/// </param>
/// <param name="valueToSend">
/// The string to send.
/// </param>
/// <param name="documentName">
/// The document name to use, if any.
/// </param>
/// <exception cref="ArgumentNullException">
/// <para><paramref name="printerName"/> is <see langword="null"/> or <see cref="string.Empty"/>.</para>
/// <para>-or-</para>
/// <para><paramref name="valueToSend"/> is <see langword="null"/> or <see cref="string.Empty"/>.</para>
/// </exception>
/// <exception cref="ArgumentException">
/// <para>The specified printer was not found.</para>
/// </exception>
/// <exception cref="Win32Exception">
/// There was an error sending the data to the printer.
/// </exception>
public static void SendStringToPrinter(string printerName, string valueToSend, string documentName)
{
if (string.IsNullOrWhiteSpace(printerName))
{
throw new ArgumentNullException(nameof(printerName));
}
if (string.IsNullOrEmpty(valueToSend))
{
throw new ArgumentNullException(nameof(valueToSend));
}
using (var printer = SafePrinterHandle.Open(printerName))
using (printer.StartDocument(documentName))
using (printer.StartPage())
{
printer.Write(valueToSend);
}
}
/// <summary>
/// Initializes all fields in the print job monitor.
/// </summary>
private void Initialize()
{
// In the event that the monitor is started while the spooler is offline,
// keep retrying until the spooler becomes available.
SafePrinterHandle hPrinter = null;
while (true)
{
try
{
void action() => hPrinter = OpenPrinter(null);
Retry.WhileThrowing <Win32Exception>(action, 5, TimeSpan.FromSeconds(30));
break;
}
catch (Win32Exception ex)
{
switch (ex.NativeErrorCode)
{
// Ignore these errors.
case RPC_S_SERVER_UNAVAILABLE:
case RPC_S_CALL_FAILED:
case ERROR_INVALID_PRINTER_NAME:
Thread.Sleep(TimeSpan.FromSeconds(1));
break;
default:
throw;
}
}
}
_options = CreatePrinterNotifyOptions();
SafePrinterChangeNotificationHandle hChange = FindFirstPrinterChangeNotification(hPrinter, PrinterChanges.Job, _options);
_hPrinters.Add(hPrinter);
_hChanges.Add(hChange);
}
internal static extern SafePrinterChangeNotificationHandle FindFirstPrinterChangeNotification(SafePrinterHandle hPrinter, uint printerChanges, uint fdwOptions, ref PrinterNotifyOptions pPrinterNotifyOptions);
internal static extern bool OpenPrinter(string pPrinterName, out SafePrinterHandle phPrinter, IntPtr pDefault);
/// <summary>
/// Creates a change notification object and returns a handle to the object.
/// </summary>
/// <param name="hPrinter">A handle to the printer or print server to monitor.</param>
/// <param name="filter">The <see cref="PrinterChanges" /> that should trigger new events.</param>
/// <param name="options">The <see cref="PrinterNotifyOptions" /> that dictate which notifications should be sent.</param>
/// <returns>A handle to a change notification object associated with the specified printer or print server.</returns>
/// <exception cref="Win32Exception">The underlying operation failed.</exception>
private static SafePrinterChangeNotificationHandle FindFirstPrinterChangeNotification(SafePrinterHandle hPrinter, PrinterChanges filter, PrinterNotifyOptions options)
{
uint fdwOptions = 0; // Must always be zero for 2D printers.
SafePrinterChangeNotificationHandle result = NativeMethods.FindFirstPrinterChangeNotification(hPrinter, (uint)filter, fdwOptions, ref options);
if (Marshal.GetLastWin32Error() > 0)
{
throw new Win32Exception();
}
return(result);
}
private static extern bool WritePrinter(SafePrinterHandle hPrinter, [MarshalAs(UnmanagedType.LPStr)] string data, int dwCount, out int dwWritten);
private static extern bool EndPagePrinter(SafePrinterHandle hPrinter);
private static extern bool StartPagePrinter(SafePrinterHandle hPrinter);
private static extern bool StartDocPrinter(SafePrinterHandle hPrinter, int level, ref DOCINFO di);
private static extern bool OpenPrinter([MarshalAs(UnmanagedType.LPWStr)] string szPrinter, out SafePrinterHandle hPrinter, IntPtr pd);
public PrinterPage(SafePrinterHandle printer)
{
_printer = printer;
}
public PrinterDocument(SafePrinterHandle printer)
{
_printer = printer;
}
