/// <summary>
/// A simpler alternative to the irritatingly useless FileSystemWatcher
/// </summary>
/// <param name="file">The file to monitor</param>
/// <param name="refreshPeriod">The refresh period.</param>
/// <param name="scheduler">The scheduler.</param>
/// <returns></returns>
public static IObservable <FileNotification> WatchFile(this FileInfo file, TimeSpan?refreshPeriod = null,
IScheduler scheduler = null)
{
return(Observable.Create <FileNotification>(observer =>
{
var refresh = refreshPeriod ?? TimeSpan.FromMilliseconds(250);
scheduler = scheduler ?? Scheduler.Default;
FileNotification notification = null;
return scheduler.ScheduleRecurringAction(refresh, () =>
{
try
{
notification = notification == null
? new FileNotification(file)
: new FileNotification(notification);
observer.OnNext(notification);
}
catch (Exception ex)
{
notification = new FileNotification(file, ex);
observer.OnNext(notification);
}
});
}).DistinctUntilChanged());
}
private FileSegmentCollection Accumulator(FileSegmentCollection previous, FileNotification current)
{
if (previous == null || previous.FileLength == 0)
{
_info = (FileInfo)current;
var fileSegments = LoadSegments().ToArray();
return(new FileSegmentCollection(_info, fileSegments, current.Size, true));
}
_info = (FileInfo)current;
return(new FileSegmentCollection(previous, _info, LoadSegments().ToArray(), current.Size, false));
}
