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Exiting c# app from splash screen

I am using a splash screen for a c# which runs on startup and checks the app license.
I show the splash from the main form like this:
public partial class Form1 : Form
{
static bool stopThreads = false;
static bool gridChanged = false;
public Form1()
{
InitializeComponent();
Thread th = new Thread(new ThreadStart(DoSplash));
th.Start();
th.Join();
}
private void DoSplash()
{
Splash sp = new Splash();
sp.ShowDialog();
}
Now from the splash form I am trying exit the application when the license is invalid, but it only exits the splash and it enters the main form.
I tried exiting with :
Enviroment.Exit();
Application.Exit();
Form1 f = new Form1();
this.Close();
But none closes the main form, only the splash.
How can I close the entire app from the splash form class?

Try Application.ExitThread()

Yes, these calls only cause the thread to exit. You created a new thread. There's little point to be gracious about it in this case, Environment.Exit(1) will get the job done. The huff-and-puff version is Control.BeginInvoke() to run code on the main UI thread. You'll need a reference to Form1 to make that call.
Btw, you'll also have a big problem with SystemEvents, they run on the wrong thread because the very first window you created was created on thread other than the main UI thread. The most typical mishap is a deadlock when you lock and unlock the work station. You'll need to wait until at least one window is created on the UI thread. Form1's OnLoad() method override or Load event would be a good place to start the splash. Or just use the built-in support for splash screens.

You could use Application.Exit() or Environment.Exit().
These probably aren't the "cleanest" way to shut down your app, but if you're just bailing at the splash screen, it's unlikely it'll cause any issues.
Edit: If you want to quit without showing the splash screen at all if the licence is invalid, you should check the licence before showing the splash screen, and just exit before then.

Never introduce multithreading in application unless absolutely necessary.
As Sir Walter put it,
Else thou shalt enter into a world of pain.
Moreover, any UI interactions, such as displaying a window or working with controls, must be done on main thread only.
If you want to do something while the form is on the screen, call Show instead of modal ShowDialog so execution does not get blocked.
Application.Exit ()
will do nicely if you call it on the main thread, as you should.
If you want to show splash screen before main form is shown, you should not do it in main form's InitializeComponent. Instead, change code in Program.cs to show splash screen first:
Application.Run (new SplashScreenForm ());
Somewhere in SplashScreenForm (I don't know why you need it at all, honestly) you should check for license, and if it's fine, close the window, create MainForm instance and call its ShowDialog. If it's bad—just close the window, and since it was the last form, application would stop.

C# WinForms child form not getting redrawn after Show()

I am working on a C# WinForms app, and I want it to be able to pop open a non-modal dialog which will get redrawn and be interactive at the same time as the main window/form.
The main window is using a SerialPort and displaying data transfer counts, which are continually increasing via a SerialDataReceivedEventHandler.
I can use ShowDialog() which seems to work in a modal fashion, but the main window data counters freeze while the dialog is in use, and I think eventually the serial buffers are overrun.
I think I want to use Show(), but if I do this the dialog appears on screen half-drawn, then is not drawn or interactive any more (gets trashed if I drag another window across it). It stays onscreen until I close the main app window.
Perhaps I should be starting another thread or, likely, am just doing something wrong. I don't usually do C# or Windows programming (maybe you can tell.)
Edit after comments (thanks, commenters):
I think maybe most things are getting run under whatever thread the serial receive event handler gets called under. When starting up my app I create a class to handle the serial, which includes:
com.DataReceived += new SerialDataReceivedEventHandler(SerialRxHandler);
The only code that I have written to care about threads is some functions to update the counters and log listbox, which I found had to be wrapped with some InvokeRequired to stop me getting complaints about thread switching:
delegate void SetCountDelegate(TextBox tb, int count);
internal void SetCount(TextBox tb, int count) {
// thread switch magic
if (InvokeRequired) {
BeginInvoke(new SetCountDelegate(SetCount), new object[] { tb, count });
} else {
tb.Text = String.Format("{0}", count);
}
}
So maybe I shouldn't be trying to Show() a form on this thread. Another InvokeRequired block, or should I be doing things completely differently?

Suppose I'll answer myself..
Prompted by commenters and a bit of thinking, I did an Invoke() to switch to the UI thread before trying to create and Show() my child dialog. That worked.

How can I execute code after my form starts?

I'm really new to Windows Forms programming and not quite sure what's the right way to go about programming.
This is my confusion.
I have a single form:
public partial class ReconcilerConsoleWindow : Form
{
public ReconcilerConsoleWindow()
{
InitializeComponent();
SetLogText("Started");
}
public void SetLogText(String text)
{
string logInfo = DateTime.Now.TimeOfDay.ToString() + ": " + text + Environment.NewLine;
tbx_Log.AppendText(logInfo);
}
}
And in my Program.cs class I have the following code:
static class Program
{
/// <summary>
/// The main entry point for the application.
/// </summary>
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
ReconcilerConsoleWindow window = new ReconcilerConsoleWindow();
Application.Run(window);
if (CallSomeMethod() == true)
{
window.SetLogText("True");
}
}
}
Now, once the window has been displayed by the Application.Run command, the program halts at that point. How can I do further processing while the window is up?
The above is just an example. My purpose is to read an XMl file and display a datagridview. Subsequently, I watch the XMl file for changes and everytime a change is made, I want to refresh the datagridview. However, once the console pops up, how can i continue with my program and make changes to the information displayed on the form on the fly?

Processing that occurs after Application.Run is usually triggered in the form's Load event handler. You can easily create a Load method in Visual Studio by double clicking any open space on the form.
This would look something like this.
private void ReconcilerConsoleWindow_Load(object sender, EventArgs e)
{
if (CallSomeMethod())
{
this.SetLogText("True");
}
}
The reason this is (as stated in several other answers) is that the main thread (the one that called Application.Run(window)) is now taken up with operating the Message Pump for the form. You can continue running things on that thread through messaging, using the form's or forms' events. Or you can start a new thread. This could be done in the main method, before you call Application.Run(window), but most people would do this in Form_Load or the form constructor, to ensure the form is set up, etc. Once Application.Run returns, all forms are now closed.

Application.Run starts the Windows event handling loop. That loop won't finish til your form closes, at which time anything you do to it won't matter anyway.
If you want to do something with your form, do it in the form's Load event handler.

Program.cs is not meant to have business rules, it should only call your Form and display it. All datagrid loading/refreshing/editing should be done at your Forms. You should be using the Events defined on Forms class, like: OnLoad, OnUnload, OnClose and many others etc.

You are missing the concept. In a Windows Forms Application, your Main Thread is responsible for running the Form.
You can always use more Threads, but in Windows Forms I would recommend using a BackgroundWorker Component for parallel Tasks:
http://msdn.microsoft.com/en-us/library/system.componentmodel.backgroundworker.aspx
Or a Timer:
http://msdn.microsoft.com/en-us/library/system.windows.forms.timer.aspx

Once Application.Run(window) is called, you'll want to handle subsequent things within the application window itself.
In the code view of the form, find the following (or add it)
private void ReconcilerConsoleWindow_Load(object sender, EventArgs e)
{
//this is where you do things :)
if (CallSomeMethod() == true)
{
window.SetLogText("True");
}
}

Exception when using secondary UI message pump for a splash screen

I have encountered an odd issue with the way I am showing a splash form, that causes an InvalidAsynchronousStateException to be thrown.
First of all, here is the code for Main{} where I start the splash form:
[STAThread]
static void Main(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Thread splash = new Thread(new ThreadStart(ShowSplash));
splash.Start();
Application.Run(new MainForm());
}
static void ShowSplash()
{
using (SplashForm splash = new SplashForm())
{
Application.Run(splash);
}
}
I am using .NET2.0, with Win XP.
During some testing where the app was left running for may hours, I noticed that the number of exceptions would occasionally increase by one or two.
(Numbers obtained by PerfMon, viewing '# of Exceps Thrown' counter.) These exceptions seem to be caught and swallowed by the runtime, because they do
not ripple up and cause anything to go wrong in the app itself. At least nothing that I can determine anyway.
I have discovered that the exception is thrown when the UserPreferenceChanged event is fired by the system. Since finding this out, I can generate the exception
at will by changing the background picture or screen saver, etc.
I am not explicitly subscribing to this event myself anywhere in code, but I understand (via the power of Google) that all top level controls and forms subscribe
to this event automatically.
I still have not determined why this event is being fired in the first place, as it appears to happen while the app is running over night, but I guess that is another mystery to be solved.
Now, if I stop the splash form thread from running, the exception disappears. Run the thread, it comes back. So, it appears that something is not unsubscribing from the event, and this is causing the subsequent exception perhaps?
Interestingly, if I substitute my splash form with a default, out of the box Form, the problem still remains:
static void ShowSplash()
{
using (Form splash = new Form())
{
Application.Run(splash);
}
}
While this form is being displayed, any UserPreferenceChanged events do not cause any exceptions. As soon as the form is closed, and the thread exits, exceptions will be thrown.
Further research has lead me to this Microsoft article, that contains the following comment:
Common causes are a splash screens
created on a secondary UI thread or
any controls created on worker
threads.
Hmm, guilty as charged by the looks of it. Note that my app is not freezing or doing anything untoward though.
At the moment, this is more of a curiosity than anything else, but I am conecerned that there may be some hidden nasties here waiting to bite in the future.
To me, it looks like the form or the message pump started by Application.Run is not cleaning up properly when it terminates.
Any thoughts?

Yes, you are running afoul with the SystemEvents class. That class creates a hidden window that listens to system events. Particularly the UserPreferenceChanged event, a lot of controls use that event to know when they need to repaint themselves because the system colors were changed.
Problem is, the initialization code that creates the window is very sensitive to the apartment state of the thread that calls it. Which in your case is wrong, you didn't call Thread.SetApartmentState() to switch to STA. That's very important for threads that display a UI.
Beware that your workaround isn't actually a fix, the system events will be raised on the wrong thread. Your splash thread instead of the UI thread of your program. You'll still get random and extremely hard to diagnose failure when an actual system event gets fired. Most infamously when the user locks the workstation, the program deadlocks when it is unlocked again.
I think calling Thread.SetApartmentState() should fix your problem. Not 100% sure, these UI thread interactions are very difficult to analyze and I haven't gotten this wrong yet. Note that .NET already has very solid support for splash screens. It definitely gets details like this right.

I was able to simulate your problem and I can offer a work around, but there might be a better option out there since this was the first time I had come across this.
One option to avoid the exception is to not actuall close the splash screen, but rather just hide it. Something like this
public partial class SplashForm : Form
{
public SplashForm()
{
InitializeComponent();
}
// Not shown here, this is wired to the FormClosing event!!!
private void SplashForm_FormClosing(object sender, FormClosingEventArgs e)
{
e.Cancel = true;
this.Hide();
}
}
Then it will be important that you make the thread that you run the splash screen on a background thread to ensure that the application is not kept alive by the splash screen thread. So your code would look something like this
[STAThread]
static void Main(string[] args)
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Thread splash = new Thread(new ThreadStart(ShowSplash));
splash.IsBackground = true;
splash.Start();
Application.Run(new MainForm());
}
static void ShowSplash()
{
using (SplashForm splash = new SplashForm())
{
Application.Run(splash);
}
}

How to prevent leaving an Icon in System Tray on exit?

My program puts an icon in the system tray because the user may minimize to it. However, if the application crashes, or I stop the app from running in VS it leaves the icon in it until I hover over it with the mouse. Sometimes I'll look down there and there will be 10 or so icons.
I can I make sure the icon goes away?

There is no way to do this. Windows does not poll your program to see if it's still alive. Therefore, your icon will stay in the system tray until you either tell it to leave (normal exit), or the user does something that initiates a call to your program (such as mouseover). Only then does the shell know that your program has died and it needs to clean up your icon.

You have several options:
1) Write a root structured exception handler that ensures the destruction of the icon before exit. This one takes some effort - but you can basically add your own unhandled exception handler to Windows which will be called in the case of many forms of "boom" which will then allow you some last-ditch clean up opportunity.
2) Write a monitor application that sleeps on your main processes handle, and kills the icon when it wakes up (the main application has died). To make this latter scenario work well, you'll likely want the main process to NOT kill the icon itself - or you could create a way to tell the monitor app that it should exit w/o destroying the icon (have the monitor app sleep on both the process handle and a named event - and if woken by the event then it simply dies w/o cleaning up after the main app).

Before you exit, set the NotifyIcon Visible property to false.

You need to call Dispose on the NotifyIcon for it to leave the tray.
EDIT: There's an event you can hook into in your Program.cs. For all Windows apps, you'll have something like this:
[STAThread]
static void Main()
{
Application.EnableVisualStyles();
Application.SetCompatibleTextRenderingDefault(false);
Application.Run(new Form1());
}
The Application class has a few events you can take advantage of to know when your app dies:
Application.ThreadException += new System.Threading.ThreadExceptionEventHandler(Application_ThreadException);
Application.ApplicationExit += new EventHandler(Application_ApplicationExit);

I don't know what happens when one kills the process, but if it crashes due to an exception, of course one can handle it. The way to do it best, depends on the type of application: Console, Forms, a service, ...
But in all cases, you should be able to use a try / finally structure in your Program.cs, and in the 'finally' section Dispose() the TrayIcon.
For example, in a Forms application, make your NotifyIcon (called TrayIcon in my example below) in your Form class public, and change the "Application.Run(new Form1())" line in Program.cs as follows:
Form form = new Form1();
try { Application.Run(form); }
finally { form.TrayIcon.Dispose(); }

We can hide trayIcon before form closing.
Add FormClosing Event
NotifyIcon ni;
...
...
private void MainForm_FormClosing(object sender, FormClosingEventArgs e)
{
ni.Visible = false;
}