新

DateTime.new(2014,10,14)
# => #<DateTime: 2014-10-14T00:00:00+00:00 ((2456945j,0s,0n),+0s,2299161j)>

当前时间：

DateTime.now
# => #<DateTime: 2016-08-04T00:43:58-03:00 ((2457605j,13438s,667386397n),-10800s,2299161j)>

请注意，它会在你的时区中显示当前时间