I've recently used quartz.net to do a few simultaneous tasks, and it feels great. Expression settings are also very flexible, but new discoveries are not ripe for expressions, and online generators are used every time.
Then wrote a WinForm version of the generator to practice practiced hand, but also to strengthen the understanding of the expression.
Of course many places draw on the online generator: http://cron.qqe2.com/, and perfected some settings.
Meaning of the expression in the garden there are already a lot of articles introduced, in this does not repeat the explanation, you can refer to quartz.net summary (ii) Crontrigger and cron expressions.
Code Open Source Address: Click Here, there are many imperfect places, and then gradually improve. Everyone wants to use a stand-alone version can be down to see.
Let's take a look at the following pictures:
quartz.net Cron Expression Builder-version WinForm