.take(num) sometimes show error

Nov 16, 2009 at 3:39 PM

err:Sequence contains no elements

I google that and others is because of using .first(), replace with .firstordefault will fix it, but i got this error when use .take(num).

Nov 16, 2009 at 3:42 PM

maybe it's because of multithread? iqtoolkit is thread-safe?