Question

I have a kept a polling timer to check if a process is running or not. I have the following simple code for this:

bool alreadyChecked = false; //check if the wait to check the second time is already over

**Timer_elapsed event**

Process sampleProcess[] = Process.GetProcessesByName("notepad");
if(sampleProcess.length > 0)
{
//Process is running
return;
}
else
{
//Process is not running, so do the following

//Wait for some time and check again (set alreadyChecked = true when the wait is over)
if (alreadyChecked){
//Run the process}
else{
//The process has started running while we were waiting
return;}
    }

I am not able to implement the waiting code inside the event, so that it can wait and then fire the event again. (Even if we implement the wait time, the Timer_elapsed event will be fired by timer again while we were waiting.)

Any suggestions?

Answer 1

You should create a separate thread and use the sleep method, using a BackgroundWorker is the best option. You can also use a timer thread.

**BackgroundWorker_DoWork event**
int nTrials = 0; // this method will help you pick any number of trials before launching the applicaion
bool isRunning = false;
while((isRunning = Process.GetProcessesByName("notepad") == 0)  || nTrials < 2)
{
    Thread.Sleep(1000); // w8 1 second before queriying the process name
    nTrials++;
} 

if ( isRunning ) RunProcess();

Don’t use the sleep method on your main thread or your application will stop handling messages for the sleep time.