ruby-on-rails - 从 End_time (UTC) 中减去 Time.now 得到一个 float (hhmmss.xx)。如何将其格式化为 HH :MM so that I can use it for a countdown timer?

Question

我有一个 end_time，我想为 end_time.utc - Time.now 创建一个计时器。但是，当我减去该值时，我得到一个类似 23510.29642 的 float ，我发现它表示小时、分钟、秒，后跟句点和毫秒。

end_time
=>  Wed, 04 Jun 2014 19:00:00 UTC +00:00 

end_time.utc - Time.now
=> -24614.329399 

如何格式化 float 以便在不手动解析字符串的情况下得到 -2:46？

Answer 1

两个时间对象之间的差异返回两次之间的秒数。

e = Time.parse("Wed, 04 Jun 2014 19:00:00 UTC +00:00")
diff = e - Time.parse("Wed, 04 Jun 2014 21:49:00 UTC +00:00")

hours = (diff / 3600).to_i
minutes = (diff / 60).to_i % 60 # if e < Time.now then minutes = (diff / 60).to_i % 60 - 60
seconds = diff.to_i % 60 # same as minutes

puts hours # -2
puts minutes # -49
puts seconds # 0