Question

I would like to know if I can get any message to say that a particular open window has gone ?

Clearify: I open a notepad, type in some text, then I close it. I would like my C# program to display a message to state that my window has gone. I am new to C# so please suggest a class or classes I may need to look into, or better provide a short sample to demonstrate the main task. I am very thankful for your help.

Answer 1

Dirty but working way will be to poll the currently running processes with a Timer, comparing the list with the processes that were running in the previous polling you made.

First, add such class member to store the processes for comparing later:

List<string> lastRunningProcesses = new List<string>();

Then, to start polling have such code:

System.Timers.Timer timer = new System.Timers.Timer();
timer.Interval = 500; //half a second
timer.Elapsed += new System.Timers.ElapsedEventHandler(timer_Elapsed);
timer.Start();

And finally this is the polling and comparing code:

void timer_Elapsed(object sender, System.Timers.ElapsedEventArgs e)
{
    List<string> currentlyRunningProcesses = System.Diagnostics.Process.GetProcesses().ToList().ConvertAll(p => p.ProcessName);
    if (lastRunningProcesses.Count > 0)
    {
        List<string> closedProcesses = lastRunningProcesses.FindAll(p => !currentlyRunningProcesses.Contains(p));
        if (closedProcesses.Count > 0)
            MessageBox.Show(string.Format("{0} process(es) have been closed:\n{1}", closedProcesses.Count, string.Join("\n", closedProcesses)));
    }
    lastRunningProcesses = currentlyRunningProcesses;
}

As long as your application will run, it will keep polling.