Printing html document from Windows Service in C # without print dialog

Question

I am using a windows service and I want to print the .html page when the service starts. I use this code and it prints well. But the print dialog appears, how can I print without the print dialog?

public void printdoc(string document) { Process printjob = new Process(); printjob.StartInfo.FileName = document; printjob.StartInfo.UseShellExecute = true; printjob.StartInfo.Verb = "print"; printjob.StartInfo.CreateNoWindow = true; printjob.StartInfo.WindowStyle = ProcessWindowStyle.Hidden; printjob.Start(); } 

Is there any other way to print this without displaying the print dialog. A.

Thanks in advance, Anup Pal

Answer 1

Here is the Holy Grail.

Using StaTaskScheduler (taken from Parallel Extension Extras ( release in the code gallery )).

Features: waiting for print completion, does not display print settings, hopefully reliable.

Limitations: requires C # 4.0, uses the default printer, does not allow changing the print pattern

  TaskScheduler Sta = new StaTaskScheduler(1); public void PrintHtml(string htmlPath) { Task.Factory.StartNew(() => PrintOnStaThread(htmlPath), CancellationToken.None, TaskCreationOptions.None, Sta).Wait(); } void PrintOnStaThread(string htmlPath) { const short PRINT_WAITFORCOMPLETION = 2; const int OLECMDID_PRINT = 6; const int OLECMDEXECOPT_DONTPROMPTUSER = 2; using(var browser = new WebBrowser()) { browser.Navigate(htmlPath); while(browser.ReadyState != WebBrowserReadyState.Complete) Application.DoEvents(); dynamic ie = browser.ActiveXInstance; ie.ExecWB(OLECMDID_PRINT, OLECMDEXECOPT_DONTPROMPTUSER, PRINT_WAITFORCOMPLETION); } } //-------------------------------------------------------------------------- // // Copyright (c) Microsoft Corporation. All rights reserved. // // File: StaTaskScheduler.cs // //-------------------------------------------------------------------------- using System.Collections.Concurrent; using System.Collections.Generic; using System.Linq; namespace System.Threading.Tasks.Schedulers { /// <summary>Provides a scheduler that uses STA threads.</summary> public sealed class StaTaskScheduler : TaskScheduler, IDisposable { /// <summary>Stores the queued tasks to be executed by our pool of STA threads.</summary> private BlockingCollection<Task> _tasks; /// <summary>The STA threads used by the scheduler.</summary> private readonly List<Thread> _threads; /// <summary>Initializes a new instance of the StaTaskScheduler class with the specified concurrency level.</summary> /// <param name="numberOfThreads">The number of threads that should be created and used by this scheduler.</param> public StaTaskScheduler(int numberOfThreads) { // Validate arguments if (numberOfThreads < 1) throw new ArgumentOutOfRangeException("concurrencyLevel"); // Initialize the tasks collection _tasks = new BlockingCollection<Task>(); // Create the threads to be used by this scheduler _threads = Enumerable.Range(0, numberOfThreads).Select(i => { var thread = new Thread(() => { // Continually get the next task and try to execute it. // This will continue until the scheduler is disposed and no more tasks remain. foreach (var t in _tasks.GetConsumingEnumerable()) { TryExecuteTask(t); } }); thread.IsBackground = true; thread.SetApartmentState(ApartmentState.STA); return thread; }).ToList(); // Start all of the threads _threads.ForEach(t => t.Start()); } /// <summary>Queues a Task to be executed by this scheduler.</summary> /// <param name="task">The task to be executed.</param> protected override void QueueTask(Task task) { // Push it into the blocking collection of tasks _tasks.Add(task); } /// <summary>Provides a list of the scheduled tasks for the debugger to consume.</summary> /// <returns>An enumerable of all tasks currently scheduled.</returns> protected override IEnumerable<Task> GetScheduledTasks() { // Serialize the contents of the blocking collection of tasks for the debugger return _tasks.ToArray(); } /// <summary>Determines whether a Task may be inlined.</summary> /// <param name="task">The task to be executed.</param> /// <param name="taskWasPreviouslyQueued">Whether the task was previously queued.</param> /// <returns>true if the task was successfully inlined; otherwise, false.</returns> protected override bool TryExecuteTaskInline(Task task, bool taskWasPreviouslyQueued) { // Try to inline if the current thread is STA return Thread.CurrentThread.GetApartmentState() == ApartmentState.STA && TryExecuteTask(task); } /// <summary>Gets the maximum concurrency level supported by this scheduler.</summary> public override int MaximumConcurrencyLevel { get { return _threads.Count; } } /// <summary> /// Cleans up the scheduler by indicating that no more tasks will be queued. /// This method blocks until all threads successfully shutdown. /// </summary> public void Dispose() { if (_tasks != null) { // Indicate that no new tasks will be coming in _tasks.CompleteAdding(); // Wait for all threads to finish processing tasks foreach (var thread in _threads) thread.Join(); // Cleanup _tasks.Dispose(); _tasks = null; } } } } 

Answer 2

To add a Vadim restriction, you can set a default printer before printing using:

  static void SetAsDefaultPrinter(string printerDevice) { foreach (var printer in PrinterSettings.InstalledPrinters) { //verify that the printer exists here } var path = "win32_printer.DeviceId='" + printerDevice + "'"; using (var printer = new ManagementObject(path)) { printer.InvokeMethod("SetDefaultPrinter", null, null); } return; } 

And slightly changing the PrintHtml method with

  public void PrintHtml(string htmlPath, string printerDevice) { if (!string.IsNullOrEmpty(printerDevice)) SetAsDefaultPrinter(printerDevice); Task.Factory.StartNew(() => PrintOnStaThread(htmlPath), CancellationToken.None, TaskCreationOptions.None, _sta).Wait(); } 

Now I do not know how this will be true in heavy printing, given that there may be a problem with concurrency when changing the default printer many times. But for now, this is the best I have come up with to fix this limitation.

Answer 3

On a Windows service, Microsoft Web Browser Management does not work. I used this code that works fine in a Windows application, but when I use in a Windows service, then the program gets stuck on this line

axWebBrowser1.Navigate (@ "C: \ mydoc.html", ref empty, ref empty, ref empty, ref empty);

thanks for the answer, Anup Pal