DateTime到Time转换中奇怪的Ruby行为

我的目标是从DateTime实例获取Time实例

这已经在这里讨论过，我仍然感到困惑： 在Ruby中转换为DateTime和Time

对我来说，运行ruby 1.9.3p0（2011-10-30修订版33570）[x86_64-darwin11.2.0]的irb运行完美

1.9.3p0 :001 > require 'Date' => true 1.9.3p0 :002 > require 'Time' => true 1.9.3p0 :003 > t=DateTime.now => # 1.9.3p0 :004 > t2=t.to_time => 2012-07-01 01:57:32 +0530 1.9.3p0 :005 > t.class => DateTime 1.9.3p0 :006 > t2.class => Time 1.9.3p0 :007 > 

但是在同一个ruby平台上使用rails console v 3.2.3时

 1.9.3p0 :001 > t=DateTime.now => Sun, 01 Jul 2012 02:00:00 +0530 1.9.3p0 :002 > t.class => DateTime 1.9.3p0 :003 > t2=t.to_time => Sun, 01 Jul 2012 02:00:00 +0530 1.9.3p0 > t2.class => DateTime 

如何从rails中的DateTime获取Time实例？

Answer 1

根据DateTime.to_time()的Rails文档 ，

如果self的偏移量不是0，那么self将不会被返回

要更改为0偏移量，请使用DateTime.utc() 。

 1.9.3p194 :005 > t3=t2.utc => Sat, 30 Jun 2012 20:43:21 +0000 1.9.3p194 :006 > t3.offset => (0/1) 1.9.3p194 :007 > t4=t3.to_time => 2012-06-30 20:43:21 UTC 1.9.3p194 :008 > t4.class => Time