async process exited not firing c# from controller

Question

I use this to run a process from a controller's action

            var psi = new ProcessStartInfo(utilityPath, String.Format("{0} {1}", inputfilePath, outputfilePath))
            {
                WorkingDirectory = Environment.CurrentDirectory,
                UseShellExecute = false,
                RedirectStandardOutput = true,
                RedirectStandardError = true,
                CreateNoWindow = true
            };

            using (var process = new Process { StartInfo = psi })
            {
                process.EnableRaisingEvents = true;
                process.OutputDataReceived += new DataReceivedEventHandler(process_OutputDataReceived);
                process.ErrorDataReceived += new DataReceivedEventHandler(process_OutputDataReceived);
                process.Exited += new EventHandler(process_Exited);

                // start the process and start reading the standard and error outputs
                process.Start();

                process.BeginErrorReadLine();
                process.BeginOutputReadLine();
                //process.WaitForExit(); //If this is commented out the delegate process_Exited never fires
            }

if i don't use process.WaitForExit(); for some reason the delegate registered here process.Exited += new EventHandler(process_Exited); never fires.

What am i doing wrong here ?

Answer 1

Handler process_Exited never fires because process variable and controller are garbage collected before the process ends. If you uncomment process.WaitForExit() then current thread will be blocked until the process ends and your controller and process variable will not be recognised as garbage and will not be collected.