Application.Restart throws InvalidOperationException

• .NET Core Version: 3.1.1

• Have you experienced this same bug with .NET Framework?: No - this has always worked fine on .NET Framework!

Problem description: Calling Application.Restart in a .NET Core WinForms application does not work as it does on .NET Framework. An exception is thrown:

System.InvalidOperationException: Process was not started by this object, so requested information cannot be determined.
   at System.Diagnostics.Process.get_StartInfo()
   at System.Windows.Forms.Application.Restart()

I also tried launching the exe without the debugger, but that doesn’t make a difference.

Additionally, there is no note or breaking change detailing any .NET Core changes.

Expected behavior: Application.Restart should work the same as it does on .NET Framework.

Minimal repro: Create a new .NET Core WinForms project in Visual Studio, put Application.Restart anywhere (even under InitializeComponent in Form1), run it, and observe the exception.

[EatonZ]

@RussKie I couldn’t get it working when I tried before, but I tried again and this time I realized why. Turns out, there is a second bug in there, but that one is already being fixed, by you!😁

I modified the method a bit and it works fine now.

private void Restart()
{
    string[] arguments = Environment.GetCommandLineArgs();
    Debug.Assert(arguments != null && arguments.Length > 0);
    StringBuilder sb = new StringBuilder((arguments.Length - 1) * 16);
    for (int argumentIndex = 1; argumentIndex < arguments.Length - 1; argumentIndex++)
    {
        sb.Append('"');
        sb.Append(arguments[argumentIndex]);
        sb.Append("\" ");
    }
    if (arguments.Length > 1)
    {
        sb.Append('"');
        sb.Append(arguments[arguments.Length - 1]);
        sb.Append('"');
    }
    ProcessStartInfo currentStartInfo = new ProcessStartInfo();
    currentStartInfo.FileName = Path.ChangeExtension(Application.ExecutablePath, "exe");
    if (sb.Length > 0)
    {
        currentStartInfo.Arguments = sb.ToString();
    }
    Application.Exit();
    Process.Start(currentStartInfo);
}

[kirsan31]

OMG, I just realized that we are using Application.Restart too 😱 Another one obstruction on migrating process 😡 @EatonZ thank you very match for workaround!!!