Ruby中處理時間的一些基本操作_ruby專題

 擷取當前日期和時間:

以下是一個簡單的例子，以獲得當前的日期和時間：

#!/usr/bin/ruby -wtime1 = Time.newputs "Current Time : " + time1.inspect# Time.now is a synonym:time2 = Time.nowputs "Current Time : " + time2.inspect

這將產生以下結果：

Current Time : Mon Jun 02 12:02:39 -0700 2008Current Time : Mon Jun 02 12:02:39 -0700 2008

擷取組件的日期和時間：

我們可以用 Time  對象來擷取日期和時間的各個組成部分。下面的例子顯示相同的：

#!/usr/bin/ruby -wtime = Time.new# Components of a Timeputs "Current Time : " + time.inspectputs time.year  # => Year of the date puts time.month  # => Month of the date (1 to 12)puts time.day   # => Day of the date (1 to 31 )puts time.wday  # => 0: Day of week: 0 is Sundayputs time.yday  # => 365: Day of yearputs time.hour  # => 23: 24-hour clockputs time.min   # => 59puts time.sec   # => 59puts time.usec  # => 999999: microsecondsputs time.zone  # => "UTC": timezone name

這將產生以下結果：

Current Time : Mon Jun 02 12:03:08 -0700 200820086211541238247476UTC

Time.utc，Time.gm和Time.local函數：

可用於這兩個函數以標準格式來格式化日期如下：

# July 8, 2008Time.local(2008, 7, 8) # July 8, 2008, 09:10am, local timeTime.local(2008, 7, 8, 9, 10)  # July 8, 2008, 09:10 UTCTime.utc(2008, 7, 8, 9, 10) # July 8, 2008, 09:10:11 GMT (same as UTC)Time.gm(2008, 7, 8, 9, 10, 11) 

下面的例子，在一個數組來擷取所有組件按以下格式：

[sec,min,hour,day,month,year,wday,yday,isdst,zone]

嘗試以下操作：

#!/usr/bin/ruby -wtime = Time.newvalues = time.to_ap values

這將產生以下結果：

[26, 10, 12, 2, 6, 2008, 1, 154, false, "MST"]

這個數組可以傳遞給Time.utc或Time.local函數得到不同的日期格式如下：

#!/usr/bin/ruby -wtime = Time.newvalues = time.to_aputs Time.utc(*values)

這將產生以下結果：

Mon Jun 02 12:15:36 UTC 2008

跟隨著的方式來獲得內部表示（依賴於平台）曆元以來的秒數時間：

# Returns number of seconds since epochtime = Time.now.to_i # Convert number of seconds into Time object.Time.at(time)# Returns second since epoch which includes microsecondstime = Time.now.to_f

時區和夏令時：

可以使用一個 Time 對象來擷取相關的所有資訊的時區和夏令如下：

time = Time.new# Here is the interpretationtime.zone    # => "UTC": return the timezonetime.utc_offset # => 0: UTC is 0 seconds offset from UTCtime.zone    # => "PST" (or whatever your timezone is)time.isdst   # => false: If UTC does not have DST.time.utc?    # => true: if t is in UTC time zonetime.localtime # Convert to local timezone.time.gmtime   # Convert back to UTC.time.getlocal  # Return a new Time object in local zonetime.getutc   # Return a new Time object in UTC

格式化時間和日期：

有各種各樣的方式來格式化日期和時間。下面是一個例子，說明幾個：

#!/usr/bin/ruby -wtime = Time.newputs time.to_sputs time.ctimeputs time.localtimeputs time.strftime("%Y-%m-%d %H:%M:%S")

這將產生以下結果：

Mon Jun 02 12:35:19 -0700 2008Mon Jun 2 12:35:19 2008Mon Jun 02 12:35:19 -0700 20082008-06-02 12:35:19

 時間算術：

可以在時間上做簡單的算術如下：

now = Time.now      # Current timeputs nowpast = now - 10     # 10 seconds ago. Time - number => Timeputs pastfuture = now + 10    # 10 seconds from now Time + number => Timeputs futurediff = future - now   # => 10 Time - Time => number of secondsputs diff

這將產生以下結果：

Thu Aug 01 20:57:05 -0700 2013Thu Aug 01 20:56:55 -0700 2013Thu Aug 01 20:57:15 -0700 201310.0