a timer stops functioning after a FileSystemWacher event occurs

Question

hi I have the following small program ============================ using System.IO; Timer tm1 = new Timer(); FileSystemWatcher wch = new FileSystemWatcher(); private void Form1_Load(object sender, System.EventArgs e) { tm1.Interval=10000; tm1.Enabled=true; tm1.Tick+= new EventHandler(TimerTick); wch.Changed += new FileSystemEventHandler(OnChanged); wch.Created += new FileSystemEventHandler(OnChanged); wch.Deleted += new FileSystemEventHandler(OnChanged); wch.Path=("c:\\temp"); wch.EnableRaisingEvents = true; } private void TimerTick(object sender, System.EventArgs e) { tm1.Enabled=false; MessageBox.Show("timer1"); tm1.Enabled=true; } private void OnChanged(object o, FileSystemEventArgs e) { tm1.Enabled=false; MessageBox.Show("file " + e.FullPath + " has been changed"); tm1.Enabled=true; } ===================== The timer tm1 functions properly untill the OnChanged event occurs then the Enable =true fails there is no error message the timer just stops responding . When i put the same enable/disable commands on another event(TimerTick) they work! what did i miss ??? thank's tami

db34 · Answer

thank's very much !! the Threading.timer Works

chrishornberger · Answer

In this function private void OnChanged(object o FileSystemEventArgs e) { tm1.Enabled=false; MessageBox.Show(file  + e.FullPath +  has been changed); tm1.Enabled=true; } You're either getting an error that is tossing you out before tm1.Enabled=true; executes (try isolating each line of code) private void OnChanged(object o FileSystemEventArgs e) { try{ tm1.Enabled=false; } catch (Exception ex) {} try{ MessageBox.Show(file  + e.FullPath +  has been changed); } catch (Exception ex) {} try{ tm1.Enabled=true; } catch (Exception ex) {} //This will become especially useful in services. } or your timer object... tm1... is being GC'd. .Enabled=false essentially turns off the timer and makes it (according to other posts I've read including from Microsoft Personnel) available for GC'ing. Try using the System.Threading.Timer object instead and instead of deactivating the timer set the timouts to Timeout.Infinite where you would normally disable your timer. You might try replacing your .Enabled calls with Stop() and Start() calls instead. I *think* they get around this issue as they do some chicanary internally that prevent GC.