protected override void OnParentUpdated(object sender, DirectoryItemUpdatedEventArgs e)
{
// If the parent path changes (i.e folder rename?),
// or its existence changes, it effects us so we need to notify subscribers we have been affected!
if ((e.OldItem.Path != e.NewItem.Path))
{
var oldItem = new FileDirectoryItem(this.FileInfo, e.OldItem as IFolderDirectoryItem, false);
OnRaiseItemUpdated(oldItem);
}
}
protected virtual void OnRaiseItemUpdated(DirectoryItemUpdatedEventArgs args)
{
// Only raise the event if the old or new item (i.e file or folder could have been renamed)
// matches a pattern.
var newItemMatches = GetMatchingFilters(args.NewItem.Path).ToArray();
var oldItemMatches = GetMatchingFilters(args.OldItem.Path).ToArray();
var unionMatches = newItemMatches.Union(oldItemMatches).ToArray();
if (unionMatches.Length > 0)
{
var watcherArgs = new DirectoryWatcherFilterMatchedEventArgs <DirectoryItemUpdatedEventArgs>(args, unionMatches);
EventHandler <DirectoryWatcherFilterMatchedEventArgs <DirectoryItemUpdatedEventArgs> > handler = ItemUpdated;
handler?.Invoke(this, watcherArgs);
}
;
}
// public event EventHandler<DirectoryItemDeletedEventArgs> ItemDeleted;
#endregion
protected void OnRaiseItemUpdated(IDirectoryItem oldItem)
{
// Make a temporary copy of the event to avoid possibility of
// a race condition if the last subscriber unsubscribes
// immediately after the null check and before the event is raised.
EventHandler <DirectoryItemUpdatedEventArgs> handler = Updated;
// Event will be null if there are no subscribers
if (handler != null)
{
var args = new DirectoryItemUpdatedEventArgs(oldItem, this);
// Use the () operator to raise the event.
handler(this, args);
}
}
/// <summary>
/// Handles an item being updated.
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
private void Item_Updated(object sender, DirectoryItemUpdatedEventArgs e)
{
// either file change, or folder rename.
// no need to register / unregister.
OnRaiseItemUpdated(e);
}
protected abstract void OnParentUpdated(object sender, DirectoryItemUpdatedEventArgs e);
