ruby - Rails 3.2.8 - 如何从 Rails 获取周数？

Question

我想知道如何从 Rails 获取当前周数以及如何操作它:

1. 将周数转换为日期。
2. 根据周数设置间隔。

谢谢。

Answer 1

使用strftime :

%U - Week number of the year. The week starts with Sunday. (00..53)
%W - Week number of the year. The week starts with Monday. (00..53)

Time.now.strftime("%U").to_i # 43

# Or...

Date.today.strftime("%U").to_i # 43

如果你想添加 43 周(或天、年、分钟等)到一个日期，你可以使用 43.weeks ，由 ActiveSupport 提供:

irb(main):001:0> 43.weeks
=> 301 days

irb(main):002:0> Date.today + 43.weeks
=> Thu, 22 Aug 2013

irb(main):003:0> Date.today + 10.days
=> Sun, 04 Nov 2012

irb(main):004:0> Date.today + 1.years # or 1.year
=> Fri, 25 Oct 2013

irb(main):005:0> Date.today + 5.months
=> Mon, 25 Mar 2013