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How can I print a pdf document from Xamarin.Forms UWP?

I have a Xamarin.Forms application that supports only UWP. I cannot find a way to print a pdf document. Whatever I have seen on the web, for some reason doesn't work for me. E.g. I tried
https://www.syncfusion.com/kb/8767/how-to-print-pdf-documents-in-xamarin-forms-platform
It lets me print, but the preview in the print dialog never shows up, and the progress indicator just keeps rotating forever.
I also tried http://zawayasoft.com/2018/03/13/uwp-print-pdf-files-silently-without-print-dialog/
This gives me errors that I cannot fix.
So I wonder if somebody can suggest something else that would actually work. Maybe something newer than what I have tried (I use VS 2017). Printing without the printing dialog would be preferable.
Thank you in advance.

I used a very dirty hack to do that!
What I had to do was to try to print the image version of the pdf (I did the conversion in backend) and then used the following DependencyInjection:
Inside my Print class in UWP project:
class Print : IPrint
{
void IPrint.Print(byte[] content)
{
Print_UWP printing = new Print_UWP();
printing.PrintUWpAsync(content);
}
}
and the class responsible for printing in uwp:
public class Print_UWP
{
PrintManager printmgr = PrintManager.GetForCurrentView();
PrintDocument PrintDoc = null;
PrintDocument printDoc;
PrintTask Task = null;
Windows.UI.Xaml.Controls.Image ViewToPrint = new Windows.UI.Xaml.Controls.Image();
public Print_UWP()
{
printmgr.PrintTaskRequested += Printmgr_PrintTaskRequested;
}
public async void PrintUWpAsync(byte[] imageData)
{
int i = 0;
while (i < 5)
{
try
{
BitmapImage biSource = new BitmapImage();
using (InMemoryRandomAccessStream stream = new InMemoryRandomAccessStream())
{
await stream.WriteAsync(imageData.AsBuffer());
stream.Seek(0);
await biSource.SetSourceAsync(stream);
}
ViewToPrint.Source = biSource;
if (PrintDoc != null)
{
printDoc.GetPreviewPage -= PrintDoc_GetPreviewPage;
printDoc.Paginate -= PrintDoc_Paginate;
printDoc.AddPages -= PrintDoc_AddPages;
}
this.printDoc = new PrintDocument();
try
{
printDoc.GetPreviewPage += PrintDoc_GetPreviewPage;
printDoc.Paginate += PrintDoc_Paginate;
printDoc.AddPages += PrintDoc_AddPages;
bool showprint = await PrintManager.ShowPrintUIAsync();
}
catch (Exception e)
{
Debug.WriteLine(e.ToString());
}
// printmgr = null;
// printDoc = null;
// Task = null;
PrintDoc = null;
GC.Collect();
printmgr.PrintTaskRequested -= Printmgr_PrintTaskRequested;
break;
}
catch (Exception e)
{
i++;
}
}
}
private void Printmgr_PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs args)
{
var deff = args.Request.GetDeferral();
Task = args.Request.CreatePrintTask("Invoice", OnPrintTaskSourceRequested);
deff.Complete();
}
async void OnPrintTaskSourceRequested(PrintTaskSourceRequestedArgs args)
{
var def = args.GetDeferral();
await Windows.ApplicationModel.Core.CoreApplication.MainView.CoreWindow.Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
args.SetSource(printDoc.DocumentSource);
});
def.Complete();
}
private void PrintDoc_AddPages(object sender, AddPagesEventArgs e)
{
printDoc.AddPage(ViewToPrint);
printDoc.AddPagesComplete();
}
private void PrintDoc_Paginate(object sender, PaginateEventArgs e)
{
PrintTaskOptions opt = Task.Options;
printDoc.SetPreviewPageCount(1, PreviewPageCountType.Final);
}
private void PrintDoc_GetPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDoc.SetPreviewPage(e.PageNumber, ViewToPrint);
}
}
Please note that this is not a perfect solution and sometimes it crashes without actually being able to trace the exception (which is really strange) so I am sure there must be better answers even though it does the job.

Print Multiple Pages From a UWA

I have about 8 records that I want to print in one batch, each on a separate page. However, the UWP sample for this uses over 600 lines of code to accomplish it. It seems to me that it has to be much, much easier than that. I thought all we'd have to do is add each page to the PrintDocument and send the print job. Apparently not. I'm using this:
async void Print()
{
var printDocument = new PrintDocument();
var printDocumentSource = printDocument.DocumentSource;
var printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested += PrintTaskRequested;
var pages = new List<Page>();
foreach (var item in items)
{
(//Set up variables)
var printPage = new PageToPrint() { //Set properties };
printPage.Set_Up(); //Set up fields
pages.Add(printPage);
}
printDocument.SetPreviewPage(1, page);
printDocument.SetPreviewPageCount(pages.Count, PreviewPageCountType.Final);
foreach (var page in pages)
{
printDocument.AddPage(page);
}
printDocument.AddPagesComplete();
await PrintManager.ShowPrintUIAsync();
}
void PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs e)
{
PrintTask printTask = null;
printTask = e.Request.CreatePrintTask("Kimble Print Job", sourceRequested =>
{
printTask.Completed += PrintTask_Completed;
sourceRequested.SetSource(printDocumentSource);
});
}
private async void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested -= PrintTaskRequested;
});
}
However, it won't generate the print preview. It just sits there spinning and spinning, and if I hit "print" it doesn't succeed (PDF can't open, job never gets to a physical printer.)
I was hoping printing would be at least reasonably easy with the PrintDocument, and I still think it looks like it should be. Am I just missing it here, or does it really take 600+ lines of code to dispatch a simple print job?

However, it won't generate the print preview.
This is because the setPreview method printDocument.SetPreviewPage(1, page); must be put in printDocument.GetPreviewPageevent handle. So you should register the event handle firstly. Same with printDocument.AddPages event handle.You messed up the event handle register and callback function all in one.Here I do a little change of your code and I tested it works well.
protected PrintDocument printDocument;
protected IPrintDocumentSource printDocumentSource;
List<Page> pages = new List<Page>();
Page printPage = new PageToPrint();
public MainPage()
{
this.InitializeComponent();
RegisterForPrinting();
}
private async void BtnPrint_Click(object sender, RoutedEventArgs e)
{
await PrintManager.ShowPrintUIAsync();
}
public void RegisterForPrinting()
{
printDocument = new PrintDocument();
printDocumentSource = printDocument.DocumentSource;
pages.Add(printPage);
printDocument.GetPreviewPage += GetPrintPreviewPage;
printDocument.AddPages += AddPrintPages;
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested += PrintTaskRequested;
}
private void AddPrintPages(object sender, AddPagesEventArgs e)
{
foreach (var page in pages)
{
printDocument.AddPage(page);
}
printDocument.AddPagesComplete();
}
private void GetPrintPreviewPage(object sender, GetPreviewPageEventArgs e)
{
printDocument.SetPreviewPage(1, printPage);
printDocument.SetPreviewPageCount(pages.Count, PreviewPageCountType.Final);
}
void PrintTaskRequested(PrintManager sender, PrintTaskRequestedEventArgs e)
{
PrintTask printTask = null;
printTask = e.Request.CreatePrintTask("Kimble Print Job", sourceRequested =>
{
printTask.Completed += PrintTask_Completed;
sourceRequested.SetSource(printDocumentSource);
});
}
private async void PrintTask_Completed(PrintTask sender, PrintTaskCompletedEventArgs args)
{
await Dispatcher.RunAsync(Windows.UI.Core.CoreDispatcherPriority.Normal, () =>
{
PrintManager printMan = PrintManager.GetForCurrentView();
printMan.PrintTaskRequested -= PrintTaskRequested;
});
}
Although you may not need all the code of the sample, but I recommend you to follow the official sample structure and build a PrintHelper class.

Run multiple winform instance sequentially

I have a C# winform application which needs to run multiple instance in synchronous way. The goal is to:
If the exe runs 3 times, it runs the first instance of the exe and the rest will wait until the first instance finishes the processing. Then, a next waiting exe intance will run and process and so on.
The exe will run one by one until it finish processing then the exe will terminates automatically af.
Any idea how to do this?
I already tried below:
private void CheckInstance()
{
bool _returnValue = true;
string _lockFile = string.Empty;
Random _rnd = new Random();
int _randomValue = _rnd.Next(100, 200);
int _rndmiliSec = 0;
_rndmiliSec = DateTime.Now.Millisecond * _rnd.Next(2, 6);
_lockFile = string.Concat(AppDomain.CurrentDomain.BaseDirectory, string.Format("/{0}", instanceFileName));
while (_returnValue)
{
_returnValue = File.Exists(_lockFile);
if (_returnValue)
{
Thread.Sleep(1000);
this.Hide();
}
else
{
try
{
Thread.Sleep((_rnd.Next(1000) + _rndmiliSec) + _rnd.Next(1000, 1500));
Functions.WriteLog(_lockFile, "Starting the process...");
Functions.WriteLog(_lockFile, string.Format("Start Time : {0}", paramPrintTime));
File.SetAttributes(_lockFile, FileAttributes.ReadOnly);
this.Show();
break;
}
catch (Exception)
{
_returnValue = false;
}
}
}
}
private void DeleteInstance()
{
try
{
File.SetAttributes(string.Concat(AppDomain.CurrentDomain.BaseDirectory, string.Format("/{0}", instanceFileName)), FileAttributes.Normal);
File.Delete(string.Concat(AppDomain.CurrentDomain.BaseDirectory, string.Format("/{0}", instanceFileName)));
}
catch (Exception)
{
}
}
private void Form_Shown(Object sender, EventArgs e)
{
_backWorker.RunWorkerAsync();
}
private void FormClosed(object sender, FormClosedEventArgs e)
{
DeleteInstance();
}
private void Form_Load(object sender, System.EventArgs e)
{
CheckInstance();
}
BackgroundWorker _backWorker = new BackgroundWorker();
public Form()
{
InitializeComponent();
_backWorker.WorkerReportsProgress = true;
_backWorker.ProgressChanged += _backWorker_ProgressChanged;
_backWorker.RunWorkerCompleted += _backWorker_RunWorkerCompleted;
_backWorker.DoWork += _backWorker_DoWork;
}
private void _backWorker_DoWork(object sender, DoWorkEventArgs e)
{
Do some work processing...
}
private void _backWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e)
{
this.Close();
}
private void _backWorker_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
pg.Value = e.ProgressPercentage;
lblIndicator.Text = e.UserState.ToString();
}
When the exe run 3 instance, the first instance will run while 2nd and third hides for a while awaiting the 1st instance to be finisih. However, after the 1st instance finish the process, The 2nd and 3rd instance are running simultaneously.
Any Ideas? Thanks.

Maybe this can work:
public static bool IsProgramRunning(string TitleOfYourForm)
{
bool result = false;
Process[] processes = Process.GetProcesses();
foreach (Process p in processes)
{
if (p.MainWindowTitle.Contains(TitleOfYourForm))
{
result = true;
break;
}
}
return result;
}
Call this function in the Main function(before opening the mainForm), if it is false Application.Exit() else show your form..
If this answer helped you, vote me.

How to program wait Custom MessageBox OK,Cancel,Yes,No responses?

How to program wait Custom MessageBox OK,Cancel,Yes,No responses? i have been using custom messageBox because of my natural language because messagebox has only english ok,yes,no i have found this one: Customizing MessageBox on Windows Phone 7
private MessageBoxService CustomMsgBox= new MessageBoxService();
public async void Handle(RecordRequest message)
{
AutoResetEvent waitHandle = new AutoResetEvent(false);
Dispatcher.BeginInvoke(() =>
{
CustomMsgBox.Closed += CustomMsgBox_Closed;
CustomMsgBox.Closed += (s, e) => waitHandle.Set();
CustomMsgBox.Show(
"Login Please! ",
"Kayıt",
MessageBoxServiceButton.OKCancel);
});
waitHandle.WaitOne();
// Must Wait MessageBox Ok or Cancel like Normal MessageBox!!!
Login.IsOpen= true;
// do something ...
}
void CustomMsgBox_Closed(object sender, EventArgs e)
{
this.CustomMsgBox.Closed -= this.CustomMsgBox_Closed;
string rst = this.CustomMsgBox.Result.ToString();
}
Normally wp8 messagebox is locked while clicking OK-Cancel. But My Costom MessageBox is not waiting. How to lock my CustomMsgBox until clicking ok-Cancel.
SAMPLE USAGE:
private PixelLab.Common.MessageBoxService _service = new PixelLab.Common.MessageBoxService();
private void Button_Click(object sender, RoutedEventArgs e)
{
this._service.Closed += this.MessageBoxService_Closed;
this._service.Show(
"test",
"alo!",
MessageBoxServiceButton.OKCancel);
//if (_service.IsOpen == true)
//{
// MessageBoxResult rslt = _service.Result;
// if (rslt == MessageBoxResult.No)
// {
// MessageBox.Show("işlem iptal edildi");
// }
// else
// {
// MessageBox.Show("işlem onaylandı");
// }
//}
}
private void MessageBoxService_Closed(object sender, EventArgs e)
{
this._service.Closed -= this.MessageBoxService_Closed;
string rst = this._service.Result.ToString();
}

systemevents.sessionended is not being caught or fired

Please in my code i try to catch win32.systemevents.sessionended event to procede with saving of my app data by the end of session in case the app is not closed manually .. some time ago this has been workin and now that i had my project grown a lil it is not any more..? i have tried to find something meaningfull for few days but found nothing really.. when i try to catch another systemevent like MonitorResolutionChanged it works well but this one not. I have also tried to register within the mainWindow (app form ..), nothing :-( Please any idea?
I think all the relevant information should be in the beginning till void Main but i put it all in case you would need or want to see more .. Thanx a lot Tomas
My code:
using System;
using System.Collections.Generic;
using System.Windows.Forms;
using System.Threading;
using MovablePython; // my own class within this project
using Avn; //my own referenced assembly
namespace DirDist
{
class Program
{
private static string appGuid = "Cddbserviceman";
private static System.Windows.Forms.ContextMenu nIMenu;
internal static System.Windows.Forms.NotifyIcon notifyIcon1;
private static MenuItem showItem;
public static MenuItem justCDsItem;
private static MenuItem searchItem;
private static MenuItem settingsItem;
private static MenuItem quitItem;
internal static Form1 mainWindow;
private static Hotkey hk;
internal static Registration.LicenceState mode; // app mode - registered/trial/blocked/demaged ..
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
using (Mutex mutex = new Mutex(false, appGuid))
{
if (!mutex.WaitOne(0, false))
{
MessageBox.Show("CDDB is already running on your machine \n (Check status bar for access ..)");
return;
}
GC.Collect();
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
mode = Registration.Startup();
Program.mainWindow = new Form1();
mainWindow.Activate();
//mainWindow.Validate();
//mainWindow.Update();
mainWindow.Visible = false;
PutIcon();
//Microsoft.Win32.SystemEvents.SessionEnded += SystemEvents_SessionEnded;
Microsoft.Win32.SystemEvents.SessionEnded += new Microsoft.Win32.SessionEndedEventHandler(SystemEvents_SessionEnded);//**zkousime zda funguje pro hibernaci ..
RegisterHotKey(true);
Application.Run();
}
}
static void SystemEvents_SessionEnded(object sender, Microsoft.Win32.SessionEndedEventArgs e)
{
//MessageBox.Show("SessionEnded fired");
RegisterHotKey(false);
notifyIcon1.Visible = false;
notifyIcon1.Dispose();
notifyIcon1 = null;
if (!mainWindow.dBSaved) mainWindow.SaveDb(Form1.settings.dBPath);
if (mainWindow.index != null) mainWindow.SaveIndex(Form1.settings.indexPath);
Microsoft.Win32.SystemEvents.SessionEnded -= new Microsoft.Win32.SessionEndedEventHandler(SystemEvents_SessionEnded);
mainWindow.Close();
}
// zaregistruje globalni hotkey ctrl+shift+F Pro hledani
private static void RegisterHotKey(bool active)
{
if (!active)
{
if (hk != null) hk.Unregister();
}
else
{
if(hk ==null) hk = new Hotkey();
hk.KeyCode = Keys.F;
//hk.Windows = true;
hk.Shift = true;
hk.Control = true;
//hk.Pressed += delegate { Console.WriteLine("Windows+1 pressed!"); };
hk.Pressed += delegate { searchItemClick(new object(), new EventArgs()); };
if (hk.GetCanRegister(mainWindow)) hk.Register(mainWindow);
else ; // just do nothing
}
}
private static void PutIcon()
{
if (notifyIcon1 == null)
{
showItem = new MenuItem ("&Show interface", new System.EventHandler (showInfaceClick));
justCDsItem = new MenuItem ("&Jus'CDs",new System.EventHandler ( justCDsClick));
justCDsItem.Checked = Form1.settings.justCDs;
searchItem = new MenuItem("Search CDDB",new System.EventHandler (searchItemClick));
searchItem.Shortcut = Shortcut.CtrlShiftF;
searchItem.ShowShortcut = true;
settingsItem = new MenuItem("Settings", new System.EventHandler(settingsItemClick));
quitItem = new MenuItem("&Quit", new System.EventHandler(quitItemClick));
nIMenu = new System.Windows.Forms.ContextMenu(new MenuItem[5] { showItem, justCDsItem, searchItem,settingsItem, quitItem });
notifyIcon1 = new System.Windows.Forms.NotifyIcon();
notifyIcon1.ContextMenu = nIMenu;
notifyIcon1.Icon = new System.Drawing.Icon(System.IO.Path.GetDirectoryName(System.Reflection.Assembly.GetExecutingAssembly().Location) + "\\Icon1.ico");
//notifyIcon1.Icon = new System.Drawing.Icon(System.IO.Path.GetDirectoryName(
//System.Reflection.Assembly.GetExecutingAssembly().GetName().CodeBase ) + "Icon1.ico");
//notifyIcon1.Icon = new System.Drawing.Icon("Icon1.ico");
notifyIcon1.DoubleClick += new EventHandler(notifyIcon1_DoubleClick);
notifyIcon1.Visible = true;
}
}
/* private static void notifyIcon1_MouseMove(object sender, MouseEventArgs mea)
* aby to fungovalo je treba upravit contextmenu na contextmenustrip a taky ty items .. az nakonec
* je tu kolem uz rozdelana priprava ..
{
notifyIcon1.ShowBalloonTip(2000,AppName,"Active",ToolTipIcon.None);
} */
// clicks on NotificationIcon context menu ..
private static void showInfaceClick(object sender, EventArgs e)
{
mainWindow.tabControl1.SelectedIndex = 0;
mainWindow.Show();
}
private static void justCDsClick(object sender, EventArgs e)
{
Form1.settings.justCDs = mainWindow.checkBox1.Checked = justCDsItem.Checked = !Form1.settings.justCDs;
if (mainWindow.Visible) mainWindow.Update();
}
private static void searchItemClick(object sender, EventArgs e)
{
mainWindow.tabControl1.SelectedIndex = 1 ;
//this.Size = new Size(this.Width, SystemInformation.PrimaryMonitorSize.Height);
mainWindow.Location = new System.Drawing.Point(SystemInformation.PrimaryMonitorSize.Width - mainWindow.Width, SystemInformation.PrimaryMonitorSize.Height - mainWindow.Height);
//mainWindow.Location = new System.Drawing.Point(880, 500);
mainWindow.Show();
}
private static void settingsItemClick(object sender, EventArgs e)
{
mainWindow.tabPage3_GotFocus(new Object(), new EventArgs());
mainWindow.tabControl1.SelectedIndex = 2;
mainWindow.Show();
}
public static void quitItemClick(object sender, EventArgs e)
{
if (DialogResult.Cancel == MessageBox.Show("Really exit application and stop scanning?",Form1.AppName,MessageBoxButtons.OKCancel,MessageBoxIcon.Question)) return;
if (!mainWindow.dBSaved) mainWindow.SaveDb(Form1.settings.dBPath);
//if (mainWindow.index != null) mainWindow.SaveIndex(Form1.settings.indexPath);
if (Form1.settings.fileIndex) mainWindow.SaveIndex(Form1.settings.indexPath);
mainWindow.Close();
mainWindow = null;
notifyIcon1.Visible = false;
Application.Exit();
}
static void notifyIcon1_DoubleClick(object sender, EventArgs e)
{
//throw new NotImplementedException();
//if (!mainWindow.Visible) mainWindow.WindowState = FormWindowState.Normal; else mainWindow.WindowState = FormWindowState.Minimized;
//if (!mainWindow.Visible) mainWindow.Show(); else mainWindow.Hide();
if (!mainWindow.Visible) mainWindow.Visible = true; else mainWindow.Visible = false;
}
}
}

OK. So here is the catch and solution . In Windows it is not determined whether win32.systemevents.sessionended shall be risen or form.close() will be called first by operating system. moreover it seems that if form.close() is called first then sessionended is omited even though form is not closed and disposed due to canceling closing process. in my system this behaviour changed after i ran some registry cleaning software. anyway understanding this we have to take care of both possible scenarios.
1. catch win32.systemevents.sessionended (or sessionending) event whatever suits our needs better and be
.
.
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Microsoft.Win32.SystemEvents.SessionEnded += new Microsoft.Win32.SessionEndedEventHandler(SystemEvents_SessionEnded);
Program.mainWindow = new Form1();
mainWindow.Activate();
mainWindow.Visible = false;
PutIcon();
RegisterHotKey(true);
Application.Run();
}
}
public static void SystemEvents_SessionEnded(object sender, Microsoft.Win32.SessionEndedEventArgs e)
{
// do whatever needed and exit application ..
RegisterHotKey(false);
notifyIcon1.Visible = false;
notifyIcon1.Dispose();
notifyIcon1 = null;
if (!mainWindow.dBSaved) mainWindow.SaveDb(Form1.settings.dBPath);
if (mainWindow.index != null) mainWindow.SaveIndex(Form1.settings.indexPath);
Microsoft.Win32.SystemEvents.SessionEnded -= new Microsoft.Win32.SessionEndedEventHandler(SystemEvents_SessionEnded);
if (mainWindow != null)
{
mainWindow.Dispose();
mainWindow = null;
}
Application.Exit();
}
2. properly override form.OnClosing() because this is being called when form is closing either manually by user or by system when shuting down, loging off etc. or create hanler for main form.Closing:
public Form1()
{
this.Closing += new CancelEventHandler(this.Form1_Closing);
InitializeComponent();
}
private void Form1_Closing(Object sender, CancelEventArgs e)
{
if (systemShutdown) Program.SystemEvents_SessionEnded(this, new Microsoft.Win32.SessionEndedEventArgs(Microsoft.Win32.SessionEndReasons.SystemShutdown));
else
{
e.Cancel = true;
this.Hide();
}
}
just want to mention that message pump must be runnig in order to sessionended be risen. Application.run() accomplishes that.
in my case as you can see i had to dig even deeper as i had closing redirected just to hide the app not to close it ( i just hide the app to notification irea icon and close it manually when i need .. ) and so i had to use some kind of way to specify the situation when this is called because sender is unfortunatelly and unexpectedly always this ..?
this is done by overring WndProc and catching propper message .here you can listen pretty much to everything inside windows ( like disc inserted / removed )but it is hooked only to a form and implementation gets often not so simple as you have to manully define various values and structs and compare against those values .. other then that its pretty simple:
private static int WM_QUERYENDSESSION = 0x11;
private static bool systemShutdown = false;
protected override void WndProc(ref System.Windows.Forms.Message m)
{
if (m.Msg==WM_QUERYENDSESSION)
{
systemShutdown = true;
}
base.WndProc(ref m);
}
this was found here:
http://msdn.microsoft.com/en-us/library/microsoft.win32.systemevents.sessionending.aspx
Thinking a bit further we can possibly omit point 1 as system shall probably always try to call mainForm.close() but i keep it as i can not be certain about windows behaviour once it runs those things in different order again .. and also it is the mainly suggested solution for reacting to system shut down ..
hope this is helpfull for someone. greets from prague tomas

Here is something that you could try
For a shutdown, override the OnShutdown method:
protected override void OnShutdown()
{
//your code here
base.OnShutdown();
}
For a logoff:
First, add an event handler to Microsoft.Win32.SystemEvents.SessionEnded in the Service Constructor:
public MyService()
{
InitializeComponent;
Microsoft.Win32.SystemEvents.SessionEnded += new Microsoft.Win32.SessionEndedEventHandler(SystemEvents_SessionEnded);
}
Then add the handler:
void SystemEvents_SessionEnded(object sender, Microsoft.Win32.SessionEndedEventArgs e)
{
//your code here
}
This should catch any ended session, including the console itself (the one running the services).