Ruby - 日期和时间

Time 类表示Ruby中的日期和时间，该类可能无法在您的系统上表示1970年之前或2038年之后的日期。

获取当前时间

以下是获取当前日期和时间的简单示例-

#!/usr/bin/ruby -w

time1=Time.new
puts "Current Time : " + time1.inspect

# Time.now is a synonym:
time2=Time.now
puts "Current Time : " + time2.inspect

这将产生以下输出-

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

获取时间组成部分

无涯教程可以使用 Time 对象获取日期和时间的各个组成部分。以下是显示相同内容的示例-

#!/usr/bin/ruby -w

time=Time.new

# Components of a Time
puts "Current Time : " + time.inspect
puts 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 Sunday
puts time.yday    # => 365: Day of year
puts time.hour    # => 23: 24-hour clock
puts time.min     # => 59
puts time.sec     # => 59
puts time.usec    # => 999999: microseconds
puts time.zone    # => "UTC": timezone name

这将产生以下输出-

Current Time : Mon Jun 02 12:03:08 -0700 2008
2008
6
2
1
154
12
3
8
247476
UTC

Time.utc,gm,local 函数

这两个函数可用于以以下标准格式格式化日期-

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

以下是以以下格式获取数组中所有组件的示例-

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

尝试以下-

#!/usr/bin/ruby -w

time=Time.new
values=time.to_a
p values

这将产生以下输出-

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

该数组可以传递给 Time.utc 或 Time.local 函数以获取不同的日期格式，如下所示:

#!/usr/bin/ruby -w

time=Time.new
values=time.to_a
puts Time.utc(*values)

这将产生以下输出-

Mon Jun 02 12:15:36 UTC 2008

以下是获取自(平台相关的)时代以来内部以秒表示的时间的方法-

# Returns number of seconds since epoch
time=Time.now.to_i  

# Convert number of seconds into Time object.
Time.at(time)

# Returns second since epoch which includes microseconds
time=Time.now.to_f

时区

您可以使用 Time 对象获取与时区相关的所有信息，如下所示-

time=Time.new

# Here is the interpretation
time.zone       # => "UTC": return the timezone
time.utc_offset # => 0: UTC is 0 seconds offset from UTC
time.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 zone
time.localtime  # Convert to local timezone.
time.gmtime     # Convert back to UTC.
time.getlocal   # Return a new Time object in local zone
time.getutc     # Return a new Time object in UTC

格式化时间和日期

有多种格式化日期和时间的方法。这是一个显示几个示例-

#!/usr/bin/ruby -w

time=Time.new
puts time.to_s
puts time.ctime
puts time.localtime
puts time.strftime("%Y-%m-%d %H:%M:%S")

这将产生以下输出-

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

时间格式指令

下表中的这些指令与方法 Time.strftime一起使用。

时间计算

您可以按时间执行简单的算术，如下所示:

now=Time.now          # Current time
puts now

past=now - 10         # 10 seconds ago. Time - number => Time
puts past

future=now + 10  # 10 seconds from now Time + number => Time
puts future

diff=future - past     # => 10  Time - Time => number of seconds
puts diff

这将产生以下输出-

Thu Aug 01 20:57:05 -0700 2013
Thu Aug 01 20:56:55 -0700 2013
Thu Aug 01 20:57:15 -0700 2013
20.0