How to Restart My C# Winform Application

How do I restart my C# WinForm Application?

Unfortunately you can't use Process.Start() to start an instance of the currently running process. According to the Process.Start() docs:
"If the process is already running, no additional process resource is started..."

This technique will work fine under the VS debugger (because VS does some kind of magic that causes Process.Start to think the process is not already running), but will fail when not run under the debugger. (Note that this may be OS-specific - I seem to remember that in some of my testing, it worked on either XP or Vista, but I may just be remembering running it under the debugger.)

This technique is exactly the one used by the last programmer on the project on which I'm currently working, and I've been trying to find a workaround for this for quite some time. So far, I've only found one solution, and it just feels dirty and kludgy to me: start a 2nd application, that waits in the background for the first application to terminate, then re-launches the 1st application. I'm sure it would work, but, yuck.

Edit: Using a 2nd application works. All I did in the second app was:

    static void RestartApp(int pid, string applicationName )
    {
        // Wait for the process to terminate
        Process process = null;
        try
        {
            process = Process.GetProcessById(pid);
            process.WaitForExit(1000);
        }
        catch (ArgumentException ex)
        {
            // ArgumentException to indicate that the 
            // process doesn't exist?   LAME!!
        }
        Process.Start(applicationName, "");
    }

(This is a very simplified example. The real code has lots of sanity checking, error handling, etc)

(C# Windows Forms Apps) How to Restart App

You have the whole game working so leave that form alone. Add another form to your project and then set the new form as the startup form. You can set it as the startup form by opening Program.cs and modifying this line:

 // Instead of Form1 put the name of your new form
Application.Run(new Form1());

Double click the new form and put this code in it:

// Note: Your load method may have a different name.
private void Form2_Load(object sender, EventArgs e)
{
    this.StartNewGame();
}

private void GameForm_FormClosed(object sender, FormClosedEventArgs e)
{
    if (MessageBox.Show("Continue?", "Continue?", MessageBoxButtons.YesNo) == DialogResult.Yes)
    {
        this.StartNewGame();
    }
}

private void StartNewGame()
{
    // Your game form may have a different name so change this to that name
    var gameForm = new Form2();
    gameForm.FormClosed += GameForm_FormClosed;
    gameForm.Show();
}

Every time the user presses the yes button on the dialog, you are creating a brand new instance of the form (of the game). In this new form, you can also have an array which keeps track of the total number of games and what the score of each game was so you can show it in case the user selected No. All you need is something like this:

var games = new List<Stats>();
// keep adding to it every time you call StartNewGame() method.

C# Application Restart

Put the dialog box like this inside the MenuItem_Click:

// restart the application once user click on Logout Menu Item
private void eToolStripMenuItem_Click(object sender, EventArgs e)
{
    //Double check if user wants to exit
    var result = MessageBox.Show("Are you sure you want to exit?", "Message",
    MessageBoxButtons.YesNo, MessageBoxIcon.Information);
    if (result == DialogResult.Yes)
    {
        Application.Restart();
    }
}

Leave your FormClosing event empty:

private void frmMain_FormClosing(object sender, FormClosingEventArgs e)
    {


    }

The other way of doing it would be if you absolutely want the dialog box to be implemented in the FormClosing event to override the OnFormClosing()

You can do this like this:

 protected override void OnFormClosing(FormClosingEventArgs e) {

        //Double check if user wants to exit
        var result = MessageBox.Show("Are you sure you want to exit?", "Message",
        MessageBoxButtons.YesNo, MessageBoxIcon.Information);
        if (result == DialogResult.Yes)
            e.Cancel = true;
            base.OnFormClosing(e);
    }

In this case also the FormClosing event will remain empty.

WinForm Application Restart?

ClickOnce handles updating an application very well. I don't see a problem here, if the user finds that the application is not working (because you have made a change server-side, that warrants them to update the client), they will restart the application and be prompted by the ClickOnce update mechanism to say an update is available (if this has been set up), once the application starts again.

The only way you could tell whether the application was due for an update, whilst the application in question is still running, is to poll the ClickOnce deployment file on the server and compare the version number against the current deployment. Not advisable.

Edit:

Another way to ensure that your users always have the most up-to-date version, is to not include a persistent deployment file and make the user always run from the launch page on your website. This would only dish out the latest and greatest version.

Restart an application by itself

I use similar code to the code you tried when restarting apps. I send a timed cmd command to restart the app for me like this:

ProcessStartInfo Info = new ProcessStartInfo();
Info.Arguments = "/C ping 127.0.0.1 -n 2 && \"" + Application.ExecutablePath + "\"";
Info.WindowStyle = ProcessWindowStyle.Hidden;
Info.CreateNoWindow = true;
Info.FileName = "cmd.exe";
Process.Start(Info);
Application.Exit(); 

The command is sent to the OS, the ping pauses the script for 2-3 seconds, by which time the application has exited from Application.Exit(), then the next command after the ping starts it again.

Note: The \" puts quotes around the path, incase it has spaces, which cmd can't process without quotes.

Hope this helps!

Restart application using C#

I don't think there's a direct method in WPF like there is in WinForms. However, you could use methods from the Windowns.Form namespace like this: (You might need to add a reference to the System.Windows.Form assembly)

System.Windows.Forms.Application.Restart();

System.Windows.Application.Current.Shutdown();

restart program if winform is not responding

You could solve this with a background thread that somehow detects that the ui thread is not responding. But how would this thread reset/restart your ui thread? This could be very difficult to do cleanly, as you would somehow have to reset all the state throughout your app to a known good condition.

So the conventional approach is instead to have a separate "watch dog" process. This can detect that your app is dead, kill its process and then run a new instance.

So how to detect that it is dead? There are many clever ways you can do this, but the simplest and most reliable is to just send a message from your app to the watch dog periodically (e.g. once per second) using a Windows forms timer - if your ui thread is busy it will not process the timer event and so the message won't be sent, and after a few seconds your watch dog will be confident that it is unresponsive, and be able to restart it.

how do I restart a single instance winforms application

Make sure that you hook on application exit event a method that releases the mutex and closes it.

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