ruby on rails - How do I get a Date from a week number?

Question

I want to find all items created in a given week, and pass in a week number param. (created_at is a normal timestamp.)

Given a week number, what is the easiest way to find a date in that particular week? (Any date in the week will do, as I will use beginning_of_week and end_of_week in the scope.)

Answer 1

You can get Date objects representing the beginning and end of your week using the commercial method:

week = 41;

wkBegin = Date.commercial(2010, week, 1)
wkEnd = Date.commercial(2010, week, 7)

Now do your find:

  Item.find(:all, :conditions->:create_date=>wkBegin..wkEnd.end_of_day)