How do I alter the timezone of a DateTime in Ruby?

Question

Reading, writing, and serializing dates and times while keeping the time zone constant is becoming annoying. I'm using Ruby (and Rails 3.0) and am trying to alter the time zone of a DateTime. (to UTC) but not the time itself.

I want this:

t = DateTime.now t.hour -> 4 t.offset = 0 t.hour -> 4 t.utc? -> true 

The closest I have come is this, but it's not intuitive.

t = DateTime.now t.hour -> 4 t += t.offset t = t.utc t.hour -> 4 t.utc? -> true 

Is there any better way?

Answer 1

Using Rails 3, you're looking for DateTime.change()

dt = DateTime.now => Mon, 20 Dec 2010 18:59:43 +0100 dt = dt.change(:offset => "+0000") => Mon, 20 Dec 2010 18:59:43 +0000