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class DateTime

Public class methods

civil_from_format(utc_or_local, year, month = 1, day = 1, hour = 0, min = 0, sec = 0)

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
Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 73
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

Public instance methods

default_inspect()

Alias for: inspect.

formatted_offset(colon = true, alternate_utc_string = nil)

Returns a formatted string of the offset from UTC, or an alternative string if the time zone is already UTC.

datetime = DateTime.civil(2000, 1, 1, 0, 0, 0, Rational(-6, 24))
datetime.formatted_offset         # => "-06:00"
datetime.formatted_offset(false)  # => "-0600"
Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 55
def formatted_offset(colon = true, alternate_utc_string = nil)
  utc? && alternate_utc_string || ActiveSupport::TimeZone.seconds_to_utc_offset(utc_offset, colon)
end

inspect()

Also aliased as: default_inspect.

Alias for: readable_inspect.

nsec()

Returns the fraction of a second as nanoseconds

Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 98
def nsec
  (sec_fraction * 1_000_000_000).to_i
end

readable_inspect()

Also aliased as: inspect.

Overrides the default inspect method with a human readable one, e.g., “Mon, 21 Feb 2005 14:30:00 +0000”.

Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 60
def readable_inspect
  to_fs(:rfc822)
end

to_f()

Converts self to a floating-point number of seconds, including fractional microseconds, since the Unix epoch.

Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 83
def to_f
  seconds_since_unix_epoch.to_f + sec_fraction
end

to_formatted_s(format = :default)

Alias for: to_fs.

to_fs(format = :default)

Also aliased as: to_formatted_s.

Convert to a formatted string. See Time::DATE_FORMATS for predefined formats.

This method is aliased to to_formatted_s.

Examples

datetime = DateTime.civil(2007, 12, 4, 0, 0, 0, 0)   # => Tue, 04 Dec 2007 00:00:00 +0000

datetime.to_fs(:db)            # => "2007-12-04 00:00:00"
datetime.to_formatted_s(:db)   # => "2007-12-04 00:00:00"
datetime.to_fs(:number)        # => "20071204000000"
datetime.to_fs(:short)         # => "04 Dec 00:00"
datetime.to_fs(:long)          # => "December 04, 2007 00:00"
datetime.to_fs(:long_ordinal)  # => "December 4th, 2007 00:00"
datetime.to_fs(:rfc822)        # => "Tue, 04 Dec 2007 00:00:00 +0000"
datetime.to_fs(:iso8601)       # => "2007-12-04T00:00:00+00:00"

Adding your own datetime formats to to_fs

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}") }
Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 35
def to_fs(format = :default)
  if formatter = ::Time::DATE_FORMATS[format]
    formatter.respond_to?(:call) ? formatter.call(self).to_s : strftime(formatter)
  else
    to_s
  end
end

to_i()

Converts self to an integer number of seconds since the Unix epoch.

Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 88
def to_i
  seconds_since_unix_epoch.to_i
end

usec()

Returns the fraction of a second as microseconds

Source code GitHub 
# File activesupport/lib/active_support/core_ext/date_time/conversions.rb, line 93
def usec
  (sec_fraction * 1_000_000).to_i
end

Definition files