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FileSystemWatcher

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FileSystemWatcher fires events on a different thread than the thread that it was registered on (mainly the UI thread). If you attempt to update a UI element (such as the FileView's treeview) you will get a "cross-thread..." exception as I showed in class. To avoid this problem, simply Set the "SynchronizingObject" property of the FileSystemWatcher to the FileView (i.e. a UI object in the Main thread) , this will force the FileSystemWatcher event callback handler to be called on the Main UI thread.

FileSystemWatcher fw = new FileSystemWatcher(path, "*.wav");
fw.EnableRaisingEvents = true;

fw.NotifyFilter = NotifyFilters.FileName;

fw.SynchronizingObject = this;

Comments

  1. Elena Oulanova9:03 PM

    I did as you told in class:
    Invoke(new MethodInvoker(() => RenewFolder(folder)));
    seems works Ok too with InvokeRequired :)
    I finished with FileSystemWatcher (halliluia!!! :)))) and probably will do config at the end because it looks yaki for me heh...

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  2. Youssef11:16 AM

    Gr8. This is the general mechanism for synchronizing any call (coming in from a non-main UI thread) back to the UI thread. I was not sure if people understood this delegate syntax.

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  3. vinny2:29 AM

    I was happy to learn how to implement the lambda approach to delegates... i bought a couple c# books at the beginning of the semester and didn't understand what they were talking about. But now I do. Also, this was a question on Stackoverflow that I could answer. My rep is up to 120 now. haha.

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