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class DateTime
Public Class Methods
Returns DateTime with local offset for given year if format is local else offset is zero.
DateTime.civil_from_format :local, 2012
# => Sun, 01 Jan 2012 00:00:00 +0300
DateTime.civil_from_format :local, 2012, 12, 17
# => Mon, 17 Dec 2012 00:00:00 +0000
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 65
def self.civil_from_format(utc_or_local, year, month=1, day=1, hour=0, min=0, sec=0)
if utc_or_local.to_sym == :local
offset = ::Time.local(year, month, day).utc_offset.to_r / 86400
else
offset = 0
end
civil(year, month, day, hour, min, sec, offset)
end
Returns Time.zone.now.to_datetime
when Time.zone
or config.time_zone
are set, otherwise returns Time.now.to_datetime
.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 8
def current
::Time.zone ? ::Time.zone.now.to_datetime : ::Time.now.to_datetime
end
Public Instance Methods
Layers additional behavior on DateTime#<=> so that Time and ActiveSupport::TimeWithZone instances can be compared with a DateTime.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 153
def <=>(other)
if other.kind_of?(Infinity)
super
elsif other.respond_to? :to_datetime
super other.to_datetime
else
nil
end
end
Duck-types as a Date-like class. See Object#acts_like?.
# File activesupport/lib/active_support/core_ext/date_time/acts_like.rb, line 6
def acts_like_date?
true
end
Duck-types as a Time-like class. See Object#acts_like?.
# File activesupport/lib/active_support/core_ext/date_time/acts_like.rb, line 11
def acts_like_time?
true
end
Uses Date to provide precise Time calculations for years, months, and days. The options
parameter takes a hash with any of these keys: :years
, :months
, :weeks
, :days
, :hours
, :minutes
, :seconds
.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 55
def advance(options)
d = to_date.advance(options)
datetime_advanced_by_date = change(:year => d.year, :month => d.month, :day => d.day)
seconds_to_advance = options.fetch(:seconds, 0) +
options.fetch(:minutes, 0) * 60 +
options.fetch(:hours, 0) * 3600
if seconds_to_advance.zero?
datetime_advanced_by_date
else
datetime_advanced_by_date.since seconds_to_advance
end
end
Returns a new DateTime representing the time a number of seconds ago. Do not use this method in combination with x.months, use months_ago instead!
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 72
def ago(seconds)
since(-seconds)
end
Returns a new DateTime representing the start of the day (0:00).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 85
def beginning_of_day
change(:hour => 0)
end
Returns a new DateTime representing the start of the hour (hh:00:00).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 109
def beginning_of_hour
change(:min => 0)
end
Returns a new DateTime representing the start of the minute (hh:mm:00).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 121
def beginning_of_minute
change(:sec => 0)
end
Returns a new DateTime where one or more of the elements have been changed according to the options
parameter. The time options (:hour
, :min
, :sec
) reset cascadingly, so if only the hour is passed, then minute and sec is set to 0. If the hour and minute is passed, then sec is set to 0. The options
parameter takes a hash with any of these keys: :year
, :month
, :day
, :hour
, :min
, :sec
, :offset
, :start
.
DateTime.new(2012, 8, 29, 22, 35, 0).change(day: 1) # => DateTime.new(2012, 8, 1, 22, 35, 0)
DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, day: 1) # => DateTime.new(1981, 8, 1, 22, 35, 0)
DateTime.new(2012, 8, 29, 22, 35, 0).change(year: 1981, hour: 0) # => DateTime.new(1981, 8, 29, 0, 0, 0)
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 38
def change(options)
::DateTime.civil(
options.fetch(:year, year),
options.fetch(:month, month),
options.fetch(:day, day),
options.fetch(:hour, hour),
options.fetch(:min, options[:hour] ? 0 : min),
options.fetch(:sec, (options[:hour] || options[:min]) ? 0 : sec + sec_fraction),
options.fetch(:offset, offset),
options.fetch(:start, start)
)
end
Returns a new DateTime representing the end of the day (23:59:59).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 103
def end_of_day
change(:hour => 23, :min => 59, :sec => 59)
end
Returns a new DateTime representing the end of the hour (hh:59:59).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 115
def end_of_hour
change(:min => 59, :sec => 59)
end
Returns a new DateTime representing the end of the minute (hh:mm:59).
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 127
def end_of_minute
change(:sec => 59)
end
datetime = DateTime.civil(2000, 1, 1, 0, 0, 0, Rational(-6, 24)) datetime.formatted_offset # => “-06:00” datetime.formatted_offset(false) # => “-0600”
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 47
def formatted_offset(colon = true, alternate_utc_string = nil)
utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
end
Returns a new DateTime representing the middle of the day (12:00)
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 93
def middle_of_day
change(:hour => 12)
end
Returns the fraction of a second as nanoseconds
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 90
def nsec
(sec_fraction * 1_000_000_000).to_i
end
Overrides the default inspect method with a human readable one, e.g., “Mon, 21 Feb 2005 14:30:00 +0000”.
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 52
def readable_inspect
to_s(:rfc822)
end
Seconds since midnight: DateTime.now.seconds_since_midnight.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 14
def seconds_since_midnight
sec + (min * 60) + (hour * 3600)
end
Returns the number of seconds until 23:59:59.
DateTime.new(2012, 8, 29, 0, 0, 0).seconds_until_end_of_day # => 86399
DateTime.new(2012, 8, 29, 12, 34, 56).seconds_until_end_of_day # => 41103
DateTime.new(2012, 8, 29, 23, 59, 59).seconds_until_end_of_day # => 0
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 23
def seconds_until_end_of_day
end_of_day.to_i - to_i
end
Returns a new DateTime representing the time a number of seconds since the instance time. Do not use this method in combination with x.months, use months_since instead!
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 79
def since(seconds)
self + Rational(seconds.round, 86400)
end
Converts self
to a floating-point number of seconds since the Unix epoch.
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 75
def to_f
seconds_since_unix_epoch.to_f
end
Convert to a formatted string. See Time::DATE_FORMATS for predefined formats.
This method is aliased to to_s
.
Examples
datetime = DateTime.civil(2007, 12, 4, 0, 0, 0, 0) # => Tue, 04 Dec 2007 00:00:00 +0000
datetime.to_formatted_s(:db) # => "2007-12-04 00:00:00"
datetime.to_s(:db) # => "2007-12-04 00:00:00"
datetime.to_s(:number) # => "20071204000000"
datetime.to_formatted_s(:short) # => "04 Dec 00:00"
datetime.to_formatted_s(:long) # => "December 04, 2007 00:00"
datetime.to_formatted_s(:long_ordinal) # => "December 4th, 2007 00:00"
datetime.to_formatted_s(:rfc822) # => "Tue, 04 Dec 2007 00:00:00 +0000"
datetime.to_formatted_s(:iso8601) # => "2007-12-04T00:00:00+00:00"
Adding your own datetime formats to #to_formatted_s
DateTime formats are shared with Time. You can add your own to the Time::DATE_FORMATS hash. Use the format name as the hash key and either a strftime string or Proc instance that takes a time or datetime argument as the value.
# config/initializers/time_formats.rb
Time::DATE_FORMATS[:month_and_year] = '%B %Y'
Time::DATE_FORMATS[:short_ordinal] = lambda { |time| time.strftime("%B #{time.day.ordinalize}") }
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 33
def to_formatted_s(format = :default)
if formatter = ::Time::DATE_FORMATS[format]
formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
else
to_default_s
end
end
Converts self
to an integer number of seconds since the Unix epoch.
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 80
def to_i
seconds_since_unix_epoch.to_i
end
Returns the fraction of a second as microseconds
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 85
def usec
(sec_fraction * 1_000_000).to_i
end
Adjusts DateTime to UTC by adding its offset value; offset is set to 0.
DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24)) # => Mon, 21 Feb 2005 10:11:12 -0600
DateTime.civil(2005, 2, 21, 10, 11, 12, Rational(-6, 24)).utc # => Mon, 21 Feb 2005 16:11:12 +0000
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 136
def utc
new_offset(0)
end
Returns true
if offset == 0
.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 142
def utc?
offset == 0
end
Returns the offset value in seconds.
# File activesupport/lib/active_support/core_ext/date_time/calculations.rb, line 147
def utc_offset
(offset * 86400).to_i
end
© 2004–2016 David Heinemeier Hansson
Licensed under the MIT License.