DateTime
¶ ↑A subclass of Date
that easily handles date, hour, minute, second, and offset.
DateTime
does not consider any leap seconds, does not track any summer time rules.
A DateTime
object is created with DateTime::new
, DateTime::jd
, DateTime::ordinal
, DateTime::commercial
, DateTime::parse
, DateTime::strptime
, DateTime::now
, Time#to_datetime
, etc.
require 'date' DateTime.new(2001,2,3,4,5,6) #=> #<DateTime: 2001-02-03T04:05:06+00:00 ...>
The last element of day, hour, minute, or second can be a fractional number. The fractional number's precision is assumed at most nanosecond.
DateTime.new(2001,2,3.5) #=> #<DateTime: 2001-02-03T12:00:00+00:00 ...>
An optional argument, the offset, indicates the difference between the local time and UTC. For example, Rational(3,24)
represents ahead of 3 hours of UTC, Rational(-5,24)
represents behind of 5 hours of UTC. The offset should be -1 to +1, and its precision is assumed at most second. The default value is zero (equals to UTC).
DateTime.new(2001,2,3,4,5,6,Rational(3,24)) #=> #<DateTime: 2001-02-03T04:05:06+03:00 ...>
The offset also accepts string form:
DateTime.new(2001,2,3,4,5,6,'+03:00') #=> #<DateTime: 2001-02-03T04:05:06+03:00 ...>
An optional argument, the day of calendar reform (start
), denotes a Julian day number, which should be 2298874 to 2426355 or negative/positive infinity. The default value is Date::ITALY
(2299161=1582-10-15).
A DateTime
object has various methods. See each reference.
d = DateTime.parse('3rd Feb 2001 04:05:06+03:30') #=> #<DateTime: 2001-02-03T04:05:06+03:30 ...> d.hour #=> 4 d.min #=> 5 d.sec #=> 6 d.offset #=> (7/48) d.zone #=> "+03:30" d += Rational('1.5') #=> #<DateTime: 2001-02-04%16:05:06+03:30 ...> d = d.new_offset('+09:00') #=> #<DateTime: 2001-02-04%21:35:06+09:00 ...> d.strftime('%I:%M:%S %p') #=> "09:35:06 PM" d > DateTime.new(1999) #=> true
DateTime
and when should you use Time
?¶ ↑It's a common misconception that William Shakespeare and Miguel de Cervantes died on the same day in history - so much so that UNESCO named April 23 as World Book Day because of this fact. However, because England hadn't yet adopted the Gregorian Calendar Reform (and wouldn't until 1752) their deaths are actually 10 days apart. Since Ruby's Time
class implements a proleptic Gregorian calendar and has no concept of calendar reform there's no way to express this with Time
objects. This is where DateTime
steps in:
shakespeare = DateTime.iso8601('1616-04-23', Date::ENGLAND) #=> Tue, 23 Apr 1616 00:00:00 +0000 cervantes = DateTime.iso8601('1616-04-23', Date::ITALY) #=> Sat, 23 Apr 1616 00:00:00 +0000
Already you can see something is weird - the days of the week are different. Taking this further:
cervantes == shakespeare #=> false (shakespeare - cervantes).to_i #=> 10
This shows that in fact they died 10 days apart (in reality 11 days since Cervantes died a day earlier but was buried on the 23rd). We can see the actual date of Shakespeare's death by using the gregorian
method to convert it:
shakespeare.gregorian #=> Tue, 03 May 1616 00:00:00 +0000
So there's an argument that all the celebrations that take place on the 23rd April in Stratford-upon-Avon are actually the wrong date since England is now using the Gregorian calendar. You can see why when we transition across the reform date boundary:
# start off with the anniversary of Shakespeare's birth in 1751 shakespeare = DateTime.iso8601('1751-04-23', Date::ENGLAND) #=> Tue, 23 Apr 1751 00:00:00 +0000 # add 366 days since 1752 is a leap year and April 23 is after February 29 shakespeare + 366 #=> Thu, 23 Apr 1752 00:00:00 +0000 # add another 365 days to take us to the anniversary in 1753 shakespeare + 366 + 365 #=> Fri, 04 May 1753 00:00:00 +0000
As you can see, if we're accurately tracking the number of solar years since Shakespeare's birthday then the correct anniversary date would be the 4th May and not the 23rd April.
So when should you use DateTime
in Ruby and when should you use Time
? Almost certainly you'll want to use Time
since your app is probably dealing with current dates and times. However, if you need to deal with dates and times in a historical context you'll want to use DateTime
to avoid making the same mistakes as UNESCO. If you also have to deal with timezones then best of luck - just bear in mind that you'll probably be dealing with local solar times, since it wasn't until the 19th century that the introduction of the railways necessitated the need for Standard Time and eventually timezones.
Parses the given representation of date and time with the given template, and returns a hash of parsed elements. _strptime does not support specification of flags and width unlike strftime.
See also strptime(3) and strftime
.
static VALUE datetime_s__strptime(int argc, VALUE *argv, VALUE klass) { return date_s__strptime_internal(argc, argv, klass, "%FT%T%z"); }
Creates a DateTime
object denoting the given calendar date.
DateTime.new(2001,2,3) #=> #<DateTime: 2001-02-03T00:00:00+00:00 ...> DateTime.new(2001,2,3,4,5,6,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.new(2001,-11,-26,-20,-55,-54,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_civil(int argc, VALUE *argv, VALUE klass) { VALUE vy, vm, vd, vh, vmin, vs, vof, vsg, y, fr, fr2, ret; int m, d, h, min, s, rof; double sg; rb_scan_args(argc, argv, "08", &vy, &vm, &vd, &vh, &vmin, &vs, &vof, &vsg); y = INT2FIX(-4712); m = 1; d = 1; h = min = s = 0; fr2 = INT2FIX(0); rof = 0; sg = DEFAULT_SG; switch (argc) { case 8: val2sg(vsg, sg); case 7: val2off(vof, rof); case 6: num2int_with_frac(s, positive_inf); case 5: num2int_with_frac(min, 5); case 4: num2int_with_frac(h, 4); case 3: num2int_with_frac(d, 3); case 2: m = NUM2INT(vm); case 1: y = vy; } if (guess_style(y, sg) < 0) { VALUE nth; int ry, rm, rd, rh, rmin, rs; if (!valid_gregorian_p(y, m, d, &nth, &ry, &rm, &rd)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); ret = d_complex_new_internal(klass, nth, 0, 0, INT2FIX(0), rof, sg, ry, rm, rd, rh, rmin, rs, HAVE_CIVIL | HAVE_TIME); } else { VALUE nth; int ry, rm, rd, rh, rmin, rs, rjd, rjd2, ns; if (!valid_civil_p(y, m, d, sg, &nth, &ry, &rm, &rd, &rjd, &ns)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); rjd2 = jd_local_to_utc(rjd, time_to_df(rh, rmin, rs), rof); ret = d_complex_new_internal(klass, nth, rjd2, 0, INT2FIX(0), rof, sg, ry, rm, rd, rh, rmin, rs, HAVE_JD | HAVE_CIVIL | HAVE_TIME); } add_frac(); return ret; }
Creates a DateTime
object denoting the given week date.
DateTime.commercial(2001) #=> #<DateTime: 2001-01-01T00:00:00+00:00 ...> DateTime.commercial(2002) #=> #<DateTime: 2001-12-31T00:00:00+00:00 ...> DateTime.commercial(2001,5,6,4,5,6,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_commercial(int argc, VALUE *argv, VALUE klass) { VALUE vy, vw, vd, vh, vmin, vs, vof, vsg, y, fr, fr2, ret; int w, d, h, min, s, rof; double sg; rb_scan_args(argc, argv, "08", &vy, &vw, &vd, &vh, &vmin, &vs, &vof, &vsg); y = INT2FIX(-4712); w = 1; d = 1; h = min = s = 0; fr2 = INT2FIX(0); rof = 0; sg = DEFAULT_SG; switch (argc) { case 8: val2sg(vsg, sg); case 7: val2off(vof, rof); case 6: num2int_with_frac(s, positive_inf); case 5: num2int_with_frac(min, 5); case 4: num2int_with_frac(h, 4); case 3: num2int_with_frac(d, 3); case 2: w = NUM2INT(vw); case 1: y = vy; } { VALUE nth; int ry, rw, rd, rh, rmin, rs, rjd, rjd2, ns; if (!valid_commercial_p(y, w, d, sg, &nth, &ry, &rw, &rd, &rjd, &ns)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); rjd2 = jd_local_to_utc(rjd, time_to_df(rh, rmin, rs), rof); ret = d_complex_new_internal(klass, nth, rjd2, 0, INT2FIX(0), rof, sg, 0, 0, 0, rh, rmin, rs, HAVE_JD | HAVE_TIME); } add_frac(); return ret; }
Creates a new DateTime
object by parsing from a string according to some RFC 2616 format.
DateTime.httpdate('Sat, 03 Feb 2001 04:05:06 GMT') #=> #<DateTime: 2001-02-03T04:05:06+00:00 ...>
static VALUE datetime_s_httpdate(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("Mon, 01 Jan -4712 00:00:00 GMT"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__httpdate(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Creates a new DateTime
object by parsing from a string according to some typical ISO 8601 formats.
DateTime.iso8601('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.iso8601('20010203T040506+0700') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.iso8601('2001-W05-6T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_iso8601(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__iso8601(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Creates a DateTime
object denoting the given chronological Julian day number.
DateTime.jd(2451944) #=> #<DateTime: 2001-02-03T00:00:00+00:00 ...> DateTime.jd(2451945) #=> #<DateTime: 2001-02-04T00:00:00+00:00 ...> DateTime.jd(Rational('0.5')) #=> #<DateTime: -4712-01-01T12:00:00+00:00 ...>
static VALUE datetime_s_jd(int argc, VALUE *argv, VALUE klass) { VALUE vjd, vh, vmin, vs, vof, vsg, jd, fr, fr2, ret; int h, min, s, rof; double sg; rb_scan_args(argc, argv, "06", &vjd, &vh, &vmin, &vs, &vof, &vsg); jd = INT2FIX(0); h = min = s = 0; fr2 = INT2FIX(0); rof = 0; sg = DEFAULT_SG; switch (argc) { case 6: val2sg(vsg, sg); case 5: val2off(vof, rof); case 4: num2int_with_frac(s, positive_inf); case 3: num2int_with_frac(min, 3); case 2: num2int_with_frac(h, 2); case 1: num2num_with_frac(jd, 1); } { VALUE nth; int rh, rmin, rs, rjd, rjd2; if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); decode_jd(jd, &nth, &rjd); rjd2 = jd_local_to_utc(rjd, time_to_df(rh, rmin, rs), rof); ret = d_complex_new_internal(klass, nth, rjd2, 0, INT2FIX(0), rof, sg, 0, 0, 0, rh, rmin, rs, HAVE_JD | HAVE_TIME); } add_frac(); return ret; }
Creates a new DateTime
object by parsing from a string according to some typical JIS X 0301 formats.
DateTime.jisx0301('H13.02.03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_jisx0301(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__jisx0301(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Creates a DateTime
object denoting the given calendar date.
DateTime.new(2001,2,3) #=> #<DateTime: 2001-02-03T00:00:00+00:00 ...> DateTime.new(2001,2,3,4,5,6,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.new(2001,-11,-26,-20,-55,-54,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_civil(int argc, VALUE *argv, VALUE klass) { VALUE vy, vm, vd, vh, vmin, vs, vof, vsg, y, fr, fr2, ret; int m, d, h, min, s, rof; double sg; rb_scan_args(argc, argv, "08", &vy, &vm, &vd, &vh, &vmin, &vs, &vof, &vsg); y = INT2FIX(-4712); m = 1; d = 1; h = min = s = 0; fr2 = INT2FIX(0); rof = 0; sg = DEFAULT_SG; switch (argc) { case 8: val2sg(vsg, sg); case 7: val2off(vof, rof); case 6: num2int_with_frac(s, positive_inf); case 5: num2int_with_frac(min, 5); case 4: num2int_with_frac(h, 4); case 3: num2int_with_frac(d, 3); case 2: m = NUM2INT(vm); case 1: y = vy; } if (guess_style(y, sg) < 0) { VALUE nth; int ry, rm, rd, rh, rmin, rs; if (!valid_gregorian_p(y, m, d, &nth, &ry, &rm, &rd)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); ret = d_complex_new_internal(klass, nth, 0, 0, INT2FIX(0), rof, sg, ry, rm, rd, rh, rmin, rs, HAVE_CIVIL | HAVE_TIME); } else { VALUE nth; int ry, rm, rd, rh, rmin, rs, rjd, rjd2, ns; if (!valid_civil_p(y, m, d, sg, &nth, &ry, &rm, &rd, &rjd, &ns)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); rjd2 = jd_local_to_utc(rjd, time_to_df(rh, rmin, rs), rof); ret = d_complex_new_internal(klass, nth, rjd2, 0, INT2FIX(0), rof, sg, ry, rm, rd, rh, rmin, rs, HAVE_JD | HAVE_CIVIL | HAVE_TIME); } add_frac(); return ret; }
Creates a DateTime
object denoting the present time.
DateTime.now #=> #<DateTime: 2011-06-11T21:20:44+09:00 ...>
static VALUE datetime_s_now(int argc, VALUE *argv, VALUE klass) { VALUE vsg, nth, ret; double sg; #ifdef HAVE_CLOCK_GETTIME struct timespec ts; #else struct timeval tv; #endif time_t sec; struct tm tm; long sf, of; int y, ry, m, d, h, min, s; rb_scan_args(argc, argv, "01", &vsg); if (argc < 1) sg = DEFAULT_SG; else sg = NUM2DBL(vsg); #ifdef HAVE_CLOCK_GETTIME if (clock_gettime(CLOCK_REALTIME, &ts) == -1) rb_sys_fail("clock_gettime"); sec = ts.tv_sec; #else if (gettimeofday(&tv, NULL) == -1) rb_sys_fail("gettimeofday"); sec = tv.tv_sec; #endif tzset(); if (!localtime_r(&sec, &tm)) rb_sys_fail("localtime"); y = tm.tm_year + 1900; m = tm.tm_mon + 1; d = tm.tm_mday; h = tm.tm_hour; min = tm.tm_min; s = tm.tm_sec; if (s == 60) s = 59; #ifdef HAVE_STRUCT_TM_TM_GMTOFF of = tm.tm_gmtoff; #elif defined(HAVE_TIMEZONE) #ifdef HAVE_ALTZONE of = (long)-((tm.tm_isdst > 0) ? altzone : timezone); #else of = (long)-timezone; if (tm.tm_isdst) { time_t sec2; tm.tm_isdst = 0; sec2 = mktime(&tm); of += (long)difftime(sec2, sec); } #endif #elif defined(HAVE_TIMEGM) { time_t sec2; sec2 = timegm(&tm); of = (long)difftime(sec2, sec); } #else { struct tm tm2; time_t sec2; if (!gmtime_r(&sec, &tm2)) rb_sys_fail("gmtime"); tm2.tm_isdst = tm.tm_isdst; sec2 = mktime(&tm2); of = (long)difftime(sec, sec2); } #endif #ifdef HAVE_CLOCK_GETTIME sf = ts.tv_nsec; #else sf = tv.tv_usec * 1000; #endif if (of < -DAY_IN_SECONDS || of > DAY_IN_SECONDS) { of = 0; rb_warning("invalid offset is ignored"); } decode_year(INT2FIX(y), -1, &nth, &ry); ret = d_complex_new_internal(klass, nth, 0, 0, LONG2NUM(sf), (int)of, GREGORIAN, ry, m, d, h, min, s, HAVE_CIVIL | HAVE_TIME); { get_d1(ret); set_sg(dat, sg); } return ret; }
Creates a DateTime
object denoting the given ordinal date.
DateTime.ordinal(2001,34) #=> #<DateTime: 2001-02-03T00:00:00+00:00 ...> DateTime.ordinal(2001,34,4,5,6,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.ordinal(2001,-332,-20,-55,-54,'+7') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_ordinal(int argc, VALUE *argv, VALUE klass) { VALUE vy, vd, vh, vmin, vs, vof, vsg, y, fr, fr2, ret; int d, h, min, s, rof; double sg; rb_scan_args(argc, argv, "07", &vy, &vd, &vh, &vmin, &vs, &vof, &vsg); y = INT2FIX(-4712); d = 1; h = min = s = 0; fr2 = INT2FIX(0); rof = 0; sg = DEFAULT_SG; switch (argc) { case 7: val2sg(vsg, sg); case 6: val2off(vof, rof); case 5: num2int_with_frac(s, positive_inf); case 4: num2int_with_frac(min, 4); case 3: num2int_with_frac(h, 3); case 2: num2int_with_frac(d, 2); case 1: y = vy; } { VALUE nth; int ry, rd, rh, rmin, rs, rjd, rjd2, ns; if (!valid_ordinal_p(y, d, sg, &nth, &ry, &rd, &rjd, &ns)) rb_raise(rb_eArgError, "invalid date"); if (!c_valid_time_p(h, min, s, &rh, &rmin, &rs)) rb_raise(rb_eArgError, "invalid date"); canon24oc(); rjd2 = jd_local_to_utc(rjd, time_to_df(rh, rmin, rs), rof); ret = d_complex_new_internal(klass, nth, rjd2, 0, INT2FIX(0), rof, sg, 0, 0, 0, rh, rmin, rs, HAVE_JD | HAVE_TIME); } add_frac(); return ret; }
Parses the given representation of date and time, and creates a DateTime
object. This method does not function as a validator.
If the optional second argument is true and the detected year is in the range “00” to “99”, makes it full.
DateTime.parse('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.parse('20010203T040506+0700') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.parse('3rd Feb 2001 04:05:06 PM') #=> #<DateTime: 2001-02-03T16:05:06+00:00 ...>
static VALUE datetime_s_parse(int argc, VALUE *argv, VALUE klass) { VALUE str, comp, sg; rb_scan_args(argc, argv, "03", &str, &comp, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: comp = Qtrue; case 2: sg = INT2FIX(DEFAULT_SG); } { VALUE argv2[2], hash; argv2[0] = str; argv2[1] = comp; hash = date_s__parse(2, argv2, klass); return dt_new_by_frags(klass, hash, sg); } }
Creates a new DateTime
object by parsing from a string according to some typical RFC 2822 formats.
DateTime.rfc2822('Sat, 3 Feb 2001 04:05:06 +0700') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_rfc2822(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("Mon, 1 Jan -4712 00:00:00 +0000"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__rfc2822(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Creates a new DateTime
object by parsing from a string according to some typical RFC 3339 formats.
DateTime.rfc3339('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_rfc3339(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__rfc3339(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Creates a new DateTime
object by parsing from a string according to some typical RFC 2822 formats.
DateTime.rfc2822('Sat, 3 Feb 2001 04:05:06 +0700') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_rfc2822(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("Mon, 1 Jan -4712 00:00:00 +0000"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__rfc2822(klass, str); return dt_new_by_frags(klass, hash, sg); } }
Parses the given representation of date and time with the given template, and creates a DateTime
object. strptime does not support specification of flags and width unlike strftime.
DateTime.strptime('2001-02-03T04:05:06+07:00', '%Y-%m-%dT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('03-02-2001 04:05:06 PM', '%d-%m-%Y %I:%M:%S %p') #=> #<DateTime: 2001-02-03T16:05:06+00:00 ...> DateTime.strptime('2001-W05-6T04:05:06+07:00', '%G-W%V-%uT%H:%M:%S%z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 04 6 04 05 06 +7', '%Y %U %w %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('2001 05 6 04 05 06 +7', '%Y %W %u %H %M %S %z') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...> DateTime.strptime('-1', '%s') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('-1000', '%Q') #=> #<DateTime: 1969-12-31T23:59:59+00:00 ...> DateTime.strptime('sat3feb014pm+7', '%a%d%b%y%H%p%z') #=> #<DateTime: 2001-02-03T16:00:00+07:00 ...>
See also strptime(3) and strftime
.
static VALUE datetime_s_strptime(int argc, VALUE *argv, VALUE klass) { VALUE str, fmt, sg; rb_scan_args(argc, argv, "03", &str, &fmt, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: fmt = rb_str_new2("%FT%T%z"); case 2: sg = INT2FIX(DEFAULT_SG); } { VALUE argv2[2], hash; argv2[0] = str; argv2[1] = fmt; hash = date_s__strptime(2, argv2, klass); return dt_new_by_frags(klass, hash, sg); } }
Creates a new DateTime
object by parsing from a string according to some typical XML Schema formats.
DateTime.xmlschema('2001-02-03T04:05:06+07:00') #=> #<DateTime: 2001-02-03T04:05:06+07:00 ...>
static VALUE datetime_s_xmlschema(int argc, VALUE *argv, VALUE klass) { VALUE str, sg; rb_scan_args(argc, argv, "02", &str, &sg); switch (argc) { case 0: str = rb_str_new2("-4712-01-01T00:00:00+00:00"); case 1: sg = INT2FIX(DEFAULT_SG); } { VALUE hash = date_s__xmlschema(klass, str); return dt_new_by_frags(klass, hash, sg); } }
This method is equivalent to strftime('%FT%T%:z'). The optional argument n
is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').iso8601(9) #=> "2001-02-03T04:05:06.123456789+07:00"
static VALUE dt_lite_iso8601(int argc, VALUE *argv, VALUE self) { long n = 0; rb_check_arity(argc, 0, 1); if (argc >= 1) n = NUM2LONG(argv[0]); return rb_str_append(strftimev("%Y-%m-%d", self, set_tmx), iso8601_timediv(self, n)); }
Returns a string in a JIS X 0301 format. The optional argument n
is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').jisx0301(9) #=> "H13.02.03T04:05:06.123456789+07:00"
static VALUE dt_lite_jisx0301(int argc, VALUE *argv, VALUE self) { long n = 0; rb_check_arity(argc, 0, 1); if (argc >= 1) n = NUM2LONG(argv[0]); return rb_str_append(d_lite_jisx0301(self), iso8601_timediv(self, n)); }
This method is equivalent to strftime('%FT%T%:z'). The optional argument n
is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').rfc3339(9) #=> "2001-02-03T04:05:06.123456789+07:00"
static VALUE dt_lite_rfc3339(int argc, VALUE *argv, VALUE self) { return dt_lite_iso8601(argc, argv, self); }
Formats date according to the directives in the given format string. The directives begin with a percent (%) character. Any text not listed as a directive will be passed through to the output string.
A directive consists of a percent (%) character, zero or more flags, an optional minimum field width, an optional modifier, and a conversion specifier as follows.
%<flags><width><modifier><conversion>
Flags:
- don't pad a numerical output. _ use spaces for padding. 0 use zeros for padding. ^ upcase the result string. # change case. : use colons for %z.
The minimum field width specifies the minimum width.
The modifiers are “E” and “O”. They are ignored.
Format directives:
Date (Year, Month, Day): %Y - Year with century (can be negative, 4 digits at least) -0001, 0000, 1995, 2009, 14292, etc. %C - year / 100 (round down. 20 in 2009) %y - year % 100 (00..99) %m - Month of the year, zero-padded (01..12) %_m blank-padded ( 1..12) %-m no-padded (1..12) %B - The full month name (``January'') %^B uppercased (``JANUARY'') %b - The abbreviated month name (``Jan'') %^b uppercased (``JAN'') %h - Equivalent to %b %d - Day of the month, zero-padded (01..31) %-d no-padded (1..31) %e - Day of the month, blank-padded ( 1..31) %j - Day of the year (001..366) Time (Hour, Minute, Second, Subsecond): %H - Hour of the day, 24-hour clock, zero-padded (00..23) %k - Hour of the day, 24-hour clock, blank-padded ( 0..23) %I - Hour of the day, 12-hour clock, zero-padded (01..12) %l - Hour of the day, 12-hour clock, blank-padded ( 1..12) %P - Meridian indicator, lowercase (``am'' or ``pm'') %p - Meridian indicator, uppercase (``AM'' or ``PM'') %M - Minute of the hour (00..59) %S - Second of the minute (00..59) %L - Millisecond of the second (000..999) %N - Fractional seconds digits, default is 9 digits (nanosecond) %3N millisecond (3 digits) %15N femtosecond (15 digits) %6N microsecond (6 digits) %18N attosecond (18 digits) %9N nanosecond (9 digits) %21N zeptosecond (21 digits) %12N picosecond (12 digits) %24N yoctosecond (24 digits) Time zone: %z - Time zone as hour and minute offset from UTC (e.g. +0900) %:z - hour and minute offset from UTC with a colon (e.g. +09:00) %::z - hour, minute and second offset from UTC (e.g. +09:00:00) %:::z - hour, minute and second offset from UTC (e.g. +09, +09:30, +09:30:30) %Z - Equivalent to %:z (e.g. +09:00) Weekday: %A - The full weekday name (``Sunday'') %^A uppercased (``SUNDAY'') %a - The abbreviated name (``Sun'') %^a uppercased (``SUN'') %u - Day of the week (Monday is 1, 1..7) %w - Day of the week (Sunday is 0, 0..6) ISO 8601 week-based year and week number: The week 1 of YYYY starts with a Monday and includes YYYY-01-04. The days in the year before the first week are in the last week of the previous year. %G - The week-based year %g - The last 2 digits of the week-based year (00..99) %V - Week number of the week-based year (01..53) Week number: The week 1 of YYYY starts with a Sunday or Monday (according to %U or %W). The days in the year before the first week are in week 0. %U - Week number of the year. The week starts with Sunday. (00..53) %W - Week number of the year. The week starts with Monday. (00..53) Seconds since the Unix Epoch: %s - Number of seconds since 1970-01-01 00:00:00 UTC. %Q - Number of milliseconds since 1970-01-01 00:00:00 UTC. Literal string: %n - Newline character (\n) %t - Tab character (\t) %% - Literal ``%'' character Combination: %c - date and time (%a %b %e %T %Y) %D - Date (%m/%d/%y) %F - The ISO 8601 date format (%Y-%m-%d) %v - VMS date (%e-%b-%Y) %x - Same as %D %X - Same as %T %r - 12-hour time (%I:%M:%S %p) %R - 24-hour time (%H:%M) %T - 24-hour time (%H:%M:%S) %+ - date(1) (%a %b %e %H:%M:%S %Z %Y)
This method is similar to the strftime() function defined in ISO C and POSIX. Several directives (%a, %A, %b, %B, %c, %p, %r, %x, %X, %E*, %O* and %Z) are locale dependent in the function. However, this method is locale independent. So, the result may differ even if the same format string is used in other systems such as C. It is good practice to avoid %x and %X because there are corresponding locale independent representations, %D and %T.
Examples:
d = DateTime.new(2007,11,19,8,37,48,"-06:00") #=> #<DateTime: 2007-11-19T08:37:48-0600 ...> d.strftime("Printed on %m/%d/%Y") #=> "Printed on 11/19/2007" d.strftime("at %I:%M%p") #=> "at 08:37AM"
Various ISO 8601 formats:
%Y%m%d => 20071119 Calendar date (basic) %F => 2007-11-19 Calendar date (extended) %Y-%m => 2007-11 Calendar date, reduced accuracy, specific month %Y => 2007 Calendar date, reduced accuracy, specific year %C => 20 Calendar date, reduced accuracy, specific century %Y%j => 2007323 Ordinal date (basic) %Y-%j => 2007-323 Ordinal date (extended) %GW%V%u => 2007W471 Week date (basic) %G-W%V-%u => 2007-W47-1 Week date (extended) %GW%V => 2007W47 Week date, reduced accuracy, specific week (basic) %G-W%V => 2007-W47 Week date, reduced accuracy, specific week (extended) %H%M%S => 083748 Local time (basic) %T => 08:37:48 Local time (extended) %H%M => 0837 Local time, reduced accuracy, specific minute (basic) %H:%M => 08:37 Local time, reduced accuracy, specific minute (extended) %H => 08 Local time, reduced accuracy, specific hour %H%M%S,%L => 083748,000 Local time with decimal fraction, comma as decimal sign (basic) %T,%L => 08:37:48,000 Local time with decimal fraction, comma as decimal sign (extended) %H%M%S.%L => 083748.000 Local time with decimal fraction, full stop as decimal sign (basic) %T.%L => 08:37:48.000 Local time with decimal fraction, full stop as decimal sign (extended) %H%M%S%z => 083748-0600 Local time and the difference from UTC (basic) %T%:z => 08:37:48-06:00 Local time and the difference from UTC (extended) %Y%m%dT%H%M%S%z => 20071119T083748-0600 Date and time of day for calendar date (basic) %FT%T%:z => 2007-11-19T08:37:48-06:00 Date and time of day for calendar date (extended) %Y%jT%H%M%S%z => 2007323T083748-0600 Date and time of day for ordinal date (basic) %Y-%jT%T%:z => 2007-323T08:37:48-06:00 Date and time of day for ordinal date (extended) %GW%V%uT%H%M%S%z => 2007W471T083748-0600 Date and time of day for week date (basic) %G-W%V-%uT%T%:z => 2007-W47-1T08:37:48-06:00 Date and time of day for week date (extended) %Y%m%dT%H%M => 20071119T0837 Calendar date and local time (basic) %FT%R => 2007-11-19T08:37 Calendar date and local time (extended) %Y%jT%H%MZ => 2007323T0837Z Ordinal date and UTC of day (basic) %Y-%jT%RZ => 2007-323T08:37Z Ordinal date and UTC of day (extended) %GW%V%uT%H%M%z => 2007W471T0837-0600 Week date and local time and difference from UTC (basic) %G-W%V-%uT%R%:z => 2007-W47-1T08:37-06:00 Week date and local time and difference from UTC (extended)
See also strftime(3) and ::strptime
.
static VALUE dt_lite_strftime(int argc, VALUE *argv, VALUE self) { return date_strftime_internal(argc, argv, self, "%Y-%m-%dT%H:%M:%S%:z", set_tmx); }
Returns a Date
object which denotes self.
static VALUE datetime_to_date(VALUE self) { get_d1a(self); if (simple_dat_p(adat)) { VALUE new = d_lite_s_alloc_simple(cDate); { get_d1b(new); bdat->s = adat->s; bdat->s.jd = m_local_jd(adat); return new; } } else { VALUE new = d_lite_s_alloc_simple(cDate); { get_d1b(new); copy_complex_to_simple(new, &bdat->s, &adat->c) bdat->s.jd = m_local_jd(adat); bdat->s.flags &= ~(HAVE_DF | HAVE_TIME | COMPLEX_DAT); return new; } } }
Returns self.
static VALUE datetime_to_datetime(VALUE self) { return self; }
Returns a string in an ISO 8601 format. (This method doesn't use the expanded representations.)
DateTime.new(2001,2,3,4,5,6,'-7').to_s #=> "2001-02-03T04:05:06-07:00"
static VALUE dt_lite_to_s(VALUE self) { return strftimev("%Y-%m-%dT%H:%M:%S%:z", self, set_tmx); }
Returns a Time
object which denotes self.
static VALUE datetime_to_time(VALUE self) { volatile VALUE dup = dup_obj(self); { VALUE t; get_d1(dup); t = rb_funcall(rb_cTime, rb_intern("new"), 7, m_real_year(dat), INT2FIX(m_mon(dat)), INT2FIX(m_mday(dat)), INT2FIX(m_hour(dat)), INT2FIX(m_min(dat)), f_add(INT2FIX(m_sec(dat)), m_sf_in_sec(dat)), INT2FIX(m_of(dat))); return t; } }
This method is equivalent to strftime('%FT%T%:z'). The optional argument n
is the number of digits for fractional seconds.
DateTime.parse('2001-02-03T04:05:06.123456789+07:00').iso8601(9) #=> "2001-02-03T04:05:06.123456789+07:00"
static VALUE dt_lite_iso8601(int argc, VALUE *argv, VALUE self) { long n = 0; rb_check_arity(argc, 0, 1); if (argc >= 1) n = NUM2LONG(argv[0]); return rb_str_append(strftimev("%Y-%m-%d", self, set_tmx), iso8601_timediv(self, n)); }