Shutdown and Logoff System Events and Windows Services

[adrianojorge]

Good Morning to all :)

Currently i'm developing a Windows Service in order to automatically send me e-mails with my remote computer operating status.
I already checked MSDN documentation about this subject http://msdn.microsoft.com/en-us/library/ycy63t34.aspx and changed the code to use on my situation. But... i don't receive e-mails from it when the remote computer is normally turned off.

Someone could help me with this issue?

The code i'm using is:

using System;
using System.ServiceProcess;
using System.Threading;
using System.Windows.Forms;
using System.Diagnostics;
using Microsoft.Win32;
using System.ComponentModel;
using System.Configuration.Install;
using System.Net.Mail;
 
namespace SimpleServiceCs
{
    public class SimpleService : ServiceBase
    {
        static void Main(string[] args)
        {
            ServiceBase.Run(new SimpleService());
        }
 
        protected override void OnStart(string[] args)
        {
            EventLog.WriteEntry("SimpleService", "Starting SimpleService");
            new Thread(RunMessagePump).Start();
        }
 
        void RunMessagePump()
        {
            EventLog.WriteEntry("SimpleService.MessagePump", "Starting SimpleService Message Pump");
            Application.Run(new HiddenForm());
        }
 
        protected override void OnStop()
        {
            Application.Exit();
        }
    }
 
    public partial class HiddenForm : Form
    {
        public HiddenForm()
        {
            InitializeComponent();
        }
 
        private void HiddenForm_Load(object sender, EventArgs e)
        {
            SystemEvents.SessionEnding += new SessionEndingEventHandler(SystemEvents_SessionEnding);
        }
 
        private void HiddenForm_FormClosing(object sender, FormClosingEventArgs e)
        {
            SystemEvents.SessionEnding -= new SessionEndingEventHandler(SystemEvents_SessionEnding);
        }
//****************************************************************************
//          THIS IS THE PART OF CODE STRANGELY NOT WORKING!?!?
//****************************************************************************
 
        private void SystemEvents_SessionEnding(object sender, EventArgs e)
        {
            EventLog.WriteEntry("System Logoff or System Shutdown");
            SendEMail("Your System is being Logged Off or Shutdown!");
        }
 
//****************************************************************************
 
        private void SendEmail(string Warning){
 
        //Here goes all the code necessary for sending e-mails from my personal mail account
 
        }
 
 
    }
 
    partial class HiddenForm
    {
        private System.ComponentModel.IContainer components = null;
 
        protected override void Dispose(bool disposing)
        {
            if (disposing && (components != null))
            {
                components.Dispose();
            }
            base.Dispose(disposing);
        }
 
        private void InitializeComponent()
        {
            this.SuspendLayout();
            this.AutoScaleDimensions = new System.Drawing.SizeF(6F, 13F);
            this.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Font;
            this.ClientSize = new System.Drawing.Size(0, 0);
            this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.None;
            this.Name = "HiddenForm";
            this.Text = "HiddenForm";
            this.WindowState = System.Windows.Forms.FormWindowState.Minimized;
            this.Load += new System.EventHandler(this.HiddenForm_Load);
            this.FormClosing += new System.Windows.Forms.FormClosingEventHandler(this.HiddenForm_FormClosing);
            this.ResumeLayout(false);
 
        }
    }
 
    [RunInstaller(true)]
    public class SimpleInstaller : Installer
    {
        private ServiceInstaller serviceInstaller;
        private ServiceProcessInstaller processInstaller;
 
        public SimpleInstaller()
        {
            processInstaller = new ServiceProcessInstaller();
            serviceInstaller = new ServiceInstaller();
 
            // Service will run under system account
            processInstaller.Account = ServiceAccount.LocalSystem;
 
            // Service will have Start Type of Manual
            serviceInstaller.StartType = ServiceStartMode.Automatic;
 
            serviceInstaller.ServiceName = "Simple Service";
 
            Installers.Add(serviceInstaller);
            Installers.Add(processInstaller);
        }
    }
}

Best Regards.

[arie]

First, when your system shuts down, it probably kills your application threads even if they didn't finish their work.

Second, using any form of interaction with GUI inside Windows service is bad bad bad! I don't know if the fact that your Form is hidden helps, or is it just "hiding" eventual problems, too. Maybe that's the problem? Why don't you just override methods that are already there, just as you override OnStart, and forget about forms?

In ServiceBase class there are methods:

protected override void OnShutdown()
protected override void OnSessionChange(SessionChangeDescription changeDescription)

and more.

[adrianojorge]

Hi Arie,

Thanks for your response.

Yes, probably it is the shutdown sequence that is not allowing my service to work correctly.

Regarding OnShutdown() method, i already tested it, but the same result... not working :(

I'm getting out of solutions for this problem. Is it possible to change the windows services shutdown sequence?

Best regards.

[arie]

Maybe, only on shutdown, try sending the mail without using other threads? I wonder if the "system shutdown sequence" will wait for the main thread of the service to complete before the service terminates?