问题
I tried doing something like
Time.now + 5.days
but that doesn't work, even though I vaguely remember seeing, and being very impressed, with being able to do something like 2.years etc.
How do I do that in Rails 3?
回答1:
Use
Time.now + 10.days
or even
10.days.from_now
Both definitely work. Are you sure you're in Rails and not just Ruby?
If you definitely are in Rails, where are you trying to run this from? Note that Active Support has to be loaded.
回答2:
days, years, etc., are part of Active Support, So this won't work in irb, but it should work in rails console.
回答3:
Some other options, just for reference
-10.days.ago
# Available in Rails 4
DateTime.now.days_ago(-10)
Just list out all options I know:
[1] Time.now + 10.days
[2] 10.days.from_now
[3] -10.days.ago
[4] DateTime.now.days_ago(-10)
[5] Date.today + 10
So now, what is the difference between them if we care about the timezone:
[1, 4]With system timezone[2, 3]With config timezone of your Rails app[5]Date only no time included in result
回答4:
This definitely works and I use this wherever I need to add days to the current date:
Date.today() + 5
回答5:
Try this on Rails
Time.new + 10.days
Try this on Ruby
require 'date'
DateTime.now.next_day(10).to_time
回答6:
Try this on Ruby. It will return a new date/time the specified number of days in the future
DateTime.now.days_since(10)
来源：https://stackoverflow.com/questions/4654457/how-to-add-10-days-to-current-time-in-rails