Date
Creates Date instances which let you work with dates and times.
If you supply no arguments, the constructor creates a Date object for today's
date and time according to local time. If you supply some arguments but not
others, the missing arguments are set to 0. If you supply any arguments, you
must supply at least the year, month, and day. You can omit the hours, minutes,
seconds, and milliseconds.
The date is measured in milliseconds since midnight 01 January, 1970 UTC. A day
holds 86,400,000 milliseconds. The Date object range is -100,000,000 days to
100,000,000 days relative to 01 January, 1970 UTC.
The Date object provides uniform behavior across platforms.
The Date object supports a number of UTC (universal) methods, as well as
local time methods. UTC, also known as Greenwich Mean Time (GMT), refers to the
time as set by the World Time Standard. The local time is the time known to the
computer where JavaScript is executed.
Invoking Date in a non-constructor context (i.e., without the new operator)
will return a string representing the current time.
Note that Date objects can only be instantiated by calling Date or using it
as a constructor; unlike other JavaScript object types, Date objects have no
literal syntax.
Several ways to assign dates
The following example shows several ways to assign dates:
today = new Date();
birthday = new Date("December 19, 1989 03:24:00");
birthday = new Date(1989,11,19);
birthday = new Date(1989,11,17,3,24,0);
Calculating elapsed time
The following examples show how to determine the elapsed time between two dates:
// using static methods
var start = Date.now();
// the event you'd like to time goes here:
doSomethingForALongTime();
var end = Date.now();
var elapsed = end - start; // time in milliseconds
// if you have Date objects
var start = new Date();
// the event you'd like to time goes here:
doSomethingForALongTime();
var end = new Date();
var elapsed = end.getTime() - start.getTime(); // time in milliseconds
// if you want to test a function and get back its return
function printElapsedTime (fTest) {
var nStartTime = Date.now(), vReturn = fTest(), nEndTime = Date.now();
alert("Elapsed time: " + String(nEndTime - nStartTime) + "
milliseconds");
return vReturn;
}
yourFunctionReturn = printElapsedTime(yourFunction);
ISO 8601 formatted dates
The following example shows how to formate a date in an ISO 8601 format using UTC:
// use a function for the exact format desired...
function ISODateString(d){
function pad(n){return n<10 ? '0'+n : n}
return d.getUTCFullYear()+'-'
+ pad(d.getUTCMonth()+1)+'-'
+ pad(d.getUTCDate())+'T'
+ pad(d.getUTCHours())+':'
+ pad(d.getUTCMinutes())+':'
+ pad(d.getUTCSeconds())+'Z'}
var d = new Date();
print(ISODateString(d)); // prints something like 2009-09-28T19:03:12Z
Methods
Instance methods Creates new Date object. ...Creates new Date object.
Parameters
- year : Number/String (optional)
Either UNIX timestamp, date string, or year (when month and day parameters also provided):
Integer value representing the number of milliseconds since 1 January 1970
00:00:00 UTC (Unix Epoch).
String value representing a date. The string should be in a format recognized
by the parse method (IETF-compliant RFC 1123 timestamps).
Integer value representing the year. For compatibility (in order to avoid the
Y2K problem), you should always specify the year in full; use 1998, rather
than 98.
- month : Number (optional)
Integer value representing the month, beginning with 0 for January to 11
for December.
- day : Number (optional)
Integer value representing the day of the month (1-31).
- hour : Number (optional)
Integer value representing the hour of the day (0-23).
- minute : Number (optional)
Integer value representing the minute segment (0-59) of a time reading.
- second : Number (optional)
Integer value representing the second segment (0-59) of a time reading.
- millisecond : Number (optional)
Integer value representing the millisecond segment (0-999) of a time reading.
Returns
Returns the day of the month for the specified date according to local time. ...Returns the day of the month for the specified date according to local time.
The second statement below assigns the value 25 to the variable day, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
day = Xmas95.getDate()
Returns
- Number
Value between 1 and 31.
Returns the day of the week for the specified date according to local time. ...Returns the day of the week for the specified date according to local time.
The value returned by getDay is an integer corresponding to the day of the week: 0 for Sunday, 1
for Monday, 2 for Tuesday, and so on.
The second statement below assigns the value 1 to weekday, based on the value of the Date
object Xmas95. December 25, 1995, is a Monday.
Xmas95 = new Date("December 25, 1995 23:15:00");
weekday = Xmas95.getDay();
Returns
- Number
A numeric representation of the day from Sunday (0) to
Saturday (6).
getFullYear( ) : NumberReturns the year of the specified date according to local time. ...Returns the year of the specified date according to local time.
The value returned by getFullYear is an absolute number. For dates between the years 1000 and
9999, getFullYear returns a four-digit number, for example, 1995. Use this function to make sure
a year is compliant with years after 2000.
Use this method instead of the getYear method.
The following example assigns the four-digit value of the current year to the variable yr.
var today = new Date();
var yr = today.getFullYear();
Returns
- Number
Four digit representation of the year.
Returns the hour for the specified date according to local time. ...Returns the hour for the specified date according to local time.
The second statement below assigns the value 23 to the variable hours, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
hours = Xmas95.getHours()
Returns
- Number
Value between 0 and 23, using 24-hour clock.
getMilliseconds( ) : NumberReturns the milliseconds in the specified date according to local time. ...Returns the milliseconds in the specified date according to local time.
The following example assigns the milliseconds portion of the current time to the variable ms.
var ms;
Today = new Date();
ms = Today.getMilliseconds();
Returns
- Number
A number between 0 and 999.
getMinutes( ) : NumberReturns the minutes in the specified date according to local time. ...Returns the minutes in the specified date according to local time.
The second statement below assigns the value 15 to the variable minutes, based on the value of
the Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
minutes = Xmas95.getMinutes()
Returns
- Number
Value between 0 and 59.
Returns the month in the specified date according to local time. ...Returns the month in the specified date according to local time.
The second statement below assigns the value 11 to the variable month, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
month = Xmas95.getMonth()
Returns
- Number
An integer between 0 and 11. 0 corresponds to January, 1 to February, and so on.
getSeconds( ) : NumberReturns the seconds in the specified date according to local time. ...Returns the seconds in the specified date according to local time.
The second statement below assigns the value 30 to the variable secs, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:30")
secs = Xmas95.getSeconds()
Returns
- Number
Value between 0 and 59.
Returns the numeric value corresponding to the time for the specified date according to
universal time. ...Returns the numeric value corresponding to the time for the specified date according to
universal time.
The value returned by the getTime method is the number of milliseconds since 1 January 1970
00:00:00 UTC. You can use this method to help assign a date and time to another Date object.
This method is functionally equivalent to the valueOf method.
Using getTime for copying dates
Constructing a date object with the identical time value.
var birthday = new Date(1994, 12, 10);
var copy = new Date();
copy.setTime(birthday.getTime());
Measuring execution time
Subtracting two subsequent getTime calls on newly generated Date objects, give the time span
between these two calls. This can be used to calculate the executing time of some operations.
var end, start;
start = new Date();
for (var i = 0; i < 1000; i++)
Math.sqrt(i);
end = new Date();
console.log("Operation took " + (end.getTime() - start.getTime()) + " msec");
Returns
- Number
Number of milliseconds since 1/1/1970 (GMT).
getTimezoneOffset( ) : NumberReturns the time-zone offset from UTC, in minutes, for the current locale. ...Returns the time-zone offset from UTC, in minutes, for the current locale.
The time-zone offset is the difference, in minutes, between UTC and local time. Note that this
means that the offset is positive if the local timezone is behind UTC and negative if it is ahead.
For example, if your time zone is UTC+10 (Australian Eastern Standard Time), -600 will be returned.
Daylight savings time prevents this value from being a constant even for a given locale
x = new Date()
currentTimeZoneOffsetInHours = x.getTimezoneOffset()/60
Returns
- Number
Minutes between GMT and local time.
getUTCDate( ) : NumberReturns the day (date) of the month in the specified date according to universal time. ...Returns the day (date) of the month in the specified date according to universal time.
The following example assigns the day portion of the current date to the variable d.
var d;
Today = new Date();
d = Today.getUTCDate();
Returns
- Number
Integer between 1 and 31 representing the day.
Returns the day of the week in the specified date according to universal time. ...Returns the day of the week in the specified date according to universal time.
The following example assigns the weekday portion of the current date to the variable weekday.
var weekday;
Today = new Date()
weekday = Today.getUTCDay()
Returns
- Number
A numeric representation of the day from Sunday (0) to
Saturday (6).
getUTCFullYear( ) : NumberReturns the year in the specified date according to universal time. ...Returns the year in the specified date according to universal time.
The following example assigns the four-digit value of the current year to the variable yr.
var yr;
Today = new Date();
yr = Today.getUTCFullYear();
Returns
- Number
Four digit representation of the year.
getUTCHours( ) : NumberReturns the hours in the specified date according to universal time. ...Returns the hours in the specified date according to universal time.
The following example assigns the hours portion of the current time to the variable hrs.
var hrs;
Today = new Date();
hrs = Today.getUTCHours();
Returns
- Number
Value between 0 and 23.
getUTCMilliseconds( ) : NumberReturns the milliseconds in the specified date according to universal time. ...Returns the milliseconds in the specified date according to universal time.
The following example assigns the milliseconds portion of the current time to the variable ms.
var ms;
Today = new Date();
ms = Today.getUTCMilliseconds();
Returns
- Number
Milliseconds portion of the Date.
getUTCMinutes( ) : NumberReturns the minutes in the specified date according to universal time. ...Returns the minutes in the specified date according to universal time.
The following example assigns the minutes portion of the current time to the variable min.
var min;
Today = new Date();
min = Today.getUTCMinutes();
Returns
- Number
Value between 0 and 59.
getUTCMonth( ) : NumberReturns the month of the specified date according to universal time. ...Returns the month of the specified date according to universal time.
The following example assigns the month portion of the current date to the variable mon.
var mon;
Today = new Date();
mon = Today.getUTCMonth();
Returns
- Number
Value between 0 (January) and 11 (December).
getUTCSeconds( ) : NumberReturns the seconds in the specified date according to universal time. ...Returns the seconds in the specified date according to universal time.
The following example assigns the seconds portion of the current time to the variable sec.
var sec;
Today = new Date();
sec = Today.getUTCSeconds();
Returns
- Number
Value between 0 and 59.
Sets the day of the month (1-31) for a specified date according to local time. ...Sets the day of the month (1-31) for a specified date according to local time.
If the parameter you specify is outside of the expected range, setDate attempts to update the
date information in the Date object accordingly. For example, if you use 0 for dayValue, the
date will be set to the last day of the previous month.
The second statement below changes the day for theBigDay to July 24 from its original value.
theBigDay = new Date("July 27, 1962 23:30:00")
theBigDay.setDate(24)
Parameters
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the full year (4 digits for 4-digit years) for a specified date according to
local time. ...Sets the full year (4 digits for 4-digit years) for a specified date according to
local time.
If you do not specify the monthValue and dayValue parameters, the values returned from the
getMonth and getDate methods are used.
If a parameter you specify is outside of the expected range, setFullYear attempts to update the
other parameters and the date information in the Date object accordingly. For example, if you
specify 15 for monthValue, the year is incremented by 1 (year + 1), and 3 is used for the month.
theBigDay = new Date();
theBigDay.setFullYear(1997);
Parameters
- yearValue : Number
An integer specifying the numeric value of the year, for example, 1995.
- monthValue : Number
An integer between 0 and 11 representing the months January through
December.
- dayValue : Number
An integer between 1 and 31 representing the day of the month. If you
specify the dayValue parameter, you must also specify the monthValue.
Returns
- Number
New date represented as milliseconds.
Sets the hours (0-23) for a specified date according to local time. ...Sets the hours (0-23) for a specified date according to local time.
If you do not specify the minutesValue, secondsValue, and msValue parameters, the values
returned from the getUTCMinutes, getUTCSeconds, and getMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setHours attempts to update the date
information in the Date object accordingly. For example, if you use 100 for secondsValue, the
minutes will be incremented by 1 (min + 1), and 40 will be used for seconds.
theBigDay.setHours(7)
Parameters
- hoursValue : Number
An integer between 0 and 23, representing the hour.
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the
secondsValue parameter, you must also specify the minutesValue.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValue parameter, you must also specify the minutesValue and secondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the milliseconds (0-999) for a specified date according to local time. ...Sets the milliseconds (0-999) for a specified date according to local time.
If you specify a number outside the expected range, the date information in the Date object is
updated accordingly. For example, if you specify 1005, the number of seconds is incremented by 1,
and 5 is used for the milliseconds.
theBigDay = new Date();
theBigDay.setMilliseconds(100);
Parameters
- millisecondsValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
Sets the minutes (0-59) for a specified date according to local time. ...Sets the minutes (0-59) for a specified date according to local time.
If you do not specify the secondsValue and msValue parameters, the values returned from
getSeconds and getMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setMinutes attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes (minutesValue) will be incremented by 1 (minutesValue + 1), and 40 will be used for
seconds.
theBigDay.setMinutes(45)
Parameters
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you
specify the secondsValue parameter, you must also specify the minutesValue.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify
the msValue parameter, you must also specify the minutesValue and secondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the month (0-11) for a specified date according to local time. ...Sets the month (0-11) for a specified date according to local time.
If you do not specify the dayValue parameter, the value returned from the getDate method is
used.
If a parameter you specify is outside of the expected range, setMonth attempts to update the date
information in the Date object accordingly. For example, if you use 15 for monthValue, the year
will be incremented by 1 (year + 1), and 3 will be used for month.
theBigDay.setMonth(6)
Parameters
- monthValue : Number
An integer between 0 and 11 (representing the months January through
December).
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the seconds (0-59) for a specified date according to local time. ...Sets the seconds (0-59) for a specified date according to local time.
If you do not specify the msValue parameter, the value returned from the getMilliseconds method
is used.
If a parameter you specify is outside of the expected range, setSeconds attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes stored in the Date object will be incremented by 1, and 40 will be used for seconds.
theBigDay.setSeconds(30)
Parameters
- secondsValue : Number
An integer between 0 and 59.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify
themsValue parameter, you must also specify the minutesValue and secondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the Date object to the time represented by a number of milliseconds since
January 1, 1970, 00:00:00 UTC, allowin...Sets the Date object to the time represented by a number of milliseconds since
January 1, 1970, 00:00:00 UTC, allowing for negative numbers for times prior.
Use the setTime method to help assign a date and time to another Date object.
theBigDay = new Date("July 1, 1999")
sameAsBigDay = new Date()
sameAsBigDay.setTime(theBigDay.getTime())
Parameters
- timeValue : Number
An integer representing the number of milliseconds since 1 January
1970, 00:00:00 UTC.
Returns
- Number
New date represented as milliseconds.
Sets the day of the month (1-31) for a specified date according to universal time. ...Sets the day of the month (1-31) for a specified date according to universal time.
If a parameter you specify is outside of the expected range, setUTCDate attempts to update the
date information in the Date object accordingly. For example, if you use 40 for dayValue, and
the month stored in the Date object is June, the day will be changed to 10 and the month will be
incremented to July.
theBigDay = new Date();
theBigDay.setUTCDate(20);
Parameters
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the full year (4 digits for 4-digit years) for a specified date according
to universal time. ...Sets the full year (4 digits for 4-digit years) for a specified date according
to universal time.
If you do not specify the monthValue and dayValue parameters, the values returned from the
getMonth and getDate methods are used.
If a parameter you specify is outside of the expected range, setUTCFullYear attempts to update
the other parameters and the date information in the Date object accordingly. For example, if you
specify 15 for monthValue, the year is incremented by 1 (year + 1), and 3 is used for the month.
theBigDay = new Date();
theBigDay.setUTCFullYear(1997);
Parameters
- yearValue : Number
An integer specifying the numeric value of the year, for example, 1995.
- monthValue : Number
An integer between 0 and 11 representing the months January through
December.
- dayValue : Number
An integer between 1 and 31 representing the day of the month. If you
specify the dayValue parameter, you must also specify the monthValue.
Returns
- Number
New date represented as milliseconds.
Sets the hour (0-23) for a specified date according to universal time. ...Sets the hour (0-23) for a specified date according to universal time.
If you do not specify the minutesValue, secondsValue, and msValue parameters, the values
returned from the getUTCMinutes, getUTCSeconds, and getUTCMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setUTCHours attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes will be incremented by 1 (min + 1), and 40 will be used for seconds.
theBigDay = new Date();
theBigDay.setUTCHours(8);
Parameters
- hoursValue : Number
An integer between 0 and 23, representing the hour.
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the
secondsValue parameter, you must also specify the minutesValue.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValue parameter, you must also specify the minutesValue and secondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the milliseconds (0-999) for a specified date according to universal time. ...Sets the milliseconds (0-999) for a specified date according to universal time.
If a parameter you specify is outside of the expected range, setUTCMilliseconds attempts to
update the date information in the Date object accordingly. For example, if you use 1100 for
millisecondsValue, the seconds stored in the Date object will be incremented by 1, and 100 will
be used for milliseconds.
theBigDay = new Date();
theBigDay.setUTCMilliseconds(500);
Parameters
- millisecondsValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
Sets the minutes (0-59) for a specified date according to universal time. ...Sets the minutes (0-59) for a specified date according to universal time.
If you do not specify the secondsValue and msValue parameters, the values returned from
getUTCSeconds and getUTCMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setUTCMinutes attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes (minutesValue) will be incremented by 1 (minutesValue + 1), and 40 will be used for
seconds.
theBigDay = new Date();
theBigDay.setUTCMinutes(43);
Parameters
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the secondsValue parameter, you must also specify the minutesValue.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the msValue parameter, you must also specify the minutesValue and secondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the month (0-11) for a specified date according to universal time. ...Sets the month (0-11) for a specified date according to universal time.
If you do not specify the dayValue parameter, the value returned from the getUTCDate method is
used.
If a parameter you specify is outside of the expected range, setUTCMonth attempts to update the
date information in the Date object accordingly. For example, if you use 15 for monthValue, the
year will be incremented by 1 (year + 1), and 3 will be used for month.
theBigDay = new Date();
theBigDay.setUTCMonth(11);
Parameters
- monthValue : Number
An integer between 0 and 11, representing the months January through
December.
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the seconds (0-59) for a specified date according to universal time. ...Sets the seconds (0-59) for a specified date according to universal time.
If you do not specify the msValue parameter, the value returned from the getUTCMilliseconds
methods is used.
If a parameter you specify is outside of the expected range, setUTCSeconds attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes stored in the Date object will be incremented by 1, and 40 will be used for seconds.
theBigDay = new Date();
theBigDay.setUTCSeconds(20);
Parameters
- secondsValue : Number
An integer between 0 and 59.
- msValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
toDateString( ) : StringReturns the "date" portion of the Date as a human-readable string in American English. ...Returns the "date" portion of the Date as a human-readable string in American English.
Date instances refer to a specific point in time. Calling toString will return the
date formatted in a human readable form in American English. In SpiderMonkey, this consists of the
date portion (day, month, and year) followed by the time portion (hours, minutes, seconds, and time
zone). Sometimes it is desirable to obtain a string of the date portion; such a thing can be
accomplished with the toDateString method.
The toDateString method is especially useful because compliant engines implementing ECMA-262 may
differ in the string obtained from toString for Date objects, as the format is implementation-
dependent and simple string slicing approaches may not produce consistent results across multiple
engines.
var d = new Date(1993, 6, 28, 14, 39, 7);
println(d.toString()); // prints Wed Jul 28 1993 14:39:07 GMT-0600 (PDT)
println(d.toDateString()); // prints Wed Jul 28 1993
Returns
- String
Human-readable string, in local time.
Returns a JSON representation of the Date object. ...Returns a JSON representation of the Date object.
Date instances refer to a specific point in time. Calling toJSON()
returns a JSON formatted string representing the Date object's
value. This method is generally intended to, by default, usefully
serialize Date objects during JSON serialization.
var jsonDate = (new Date()).toJSON();
var backToDate = new Date(jsonDate);
console.log("Serialized date object: " + jsonDate);
// Serialized date object: 2013-01-17T12:59:08.449Z
NOTE: This method is part of the ECMAScript 5 standard.
Returns
- String
Date value in YYYY-MM-DDTHH-MM-SS.MMMZ format.
toLocaleDateString( ) : StringReturns the "date" portion of the Date as a string, using the current locale's
conventions. ...Returns the "date" portion of the Date as a string, using the current locale's
conventions.
The toLocaleDateString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98). If the operating system is not
year-2000 compliant and does not use the full year for years before 1900 or over 2000,
toLocaleDateString returns a string that is not year-2000 compliant. toLocaleDateString behaves
similarly to toString when converting a year that the operating system does not properly format.
Methods such as getDate, getMonth, and getFullYear give more portable results than
toLocaleDateString. Use toLocaleDateString when the intent is to display to the user a string
formatted using the regional format chosen by the user. Be aware that this method, due to its
nature, behaves differently depending on the operating system and on the user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35) //months are represented by 0 to 11
today.toLocaleDateString()
In this example, toLocaleDateString returns a string value that is similar to the following form.
The exact format depends on the platform, locale and user's settings.
12/18/95
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleDateString(); // Good example
"Last visit was at " + someDate.toLocaleDateString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending
on the country.
toLocaleString( ) : StringConverts a date to a string, using the current locale's conventions. ...Converts a date to a string, using the current locale's conventions. Overrides
the Object.toLocaleString method.
The toLocaleString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98). If the operating system is not
year-2000 compliant and does not use the full year for years before 1900 or over 2000,
toLocaleString returns a string that is not year-2000 compliant. toLocaleString behaves
similarly to toString when converting a year that the operating system does not properly format.
Methods such as getDate, getMonth, getFullYear, getHours, getMinutes, and getSeconds
give more portable results than toLocaleString. Use toLocaleString when the intent is to
display to the user a string formatted using the regional format chosen by the user. Be aware that
this method, due to its nature, behaves differently depending on the operating system and on the
user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35); //months are represented by 0 to 11
today.toLocaleString();
In this example, toLocaleString returns a string value that is similar to the following form. The
exact format depends on the platform, locale and user's settings.
12/18/95 17:28:35
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleString(); // Good example
"Last visit was at " + someDate.toLocaleString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending
on the country.
toLocaleTimeString( ) : StringReturns the "time" portion of the Date as a string, using the current locale's
conventions. ...Returns the "time" portion of the Date as a string, using the current locale's
conventions.
The toLocaleTimeString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98).
Methods such as getHours, getMinutes, and getSeconds give more consistent results than
toLocaleTimeString. Use toLocaleTimeString when the intent is to display to the user a string
formatted using the regional format chosen by the user. Be aware that this method, due to its
nature, behaves differently depending on the operating system and on the user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35) //months are represented by 0 to 11
today.toLocaleTimeString()
In this example, toLocaleTimeString returns a string value that is similar to the following form.
The exact format depends on the platform.
17:28:35
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleTimeString(); // Good example
"Last visit was at " + someDate.toLocaleTimeString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending
on the country.
Returns a string representing the specified Date object. ...Returns a string representing the specified Date object. Overrides the
Object.prototype.toString method.
The Date object overrides the toString method of the Object object; it does not inherit
Object.toString. For Date objects, the toString method returns a string representation of the
object.
toString always returns a string representation of the date in American English.
JavaScript calls the toString method automatically when a date is to be represented as a text
value or when a date is referred to in a string concatenation.
The following assigns the toString value of a Date object to myVar:
x = new Date();
myVar=x.toString(); //assigns a value to myVar similar to:
//Mon Sep 28 1998 14:36:22 GMT-0700 (Pacific Daylight Time)
Returns
- String
Human-readable string of the date in local time.
toTimeString( ) : StringReturns the "time" portion of the Date as a human-readable string. ...Returns the "time" portion of the Date as a human-readable string.
Date instances refer to a specific point in time. Calling toString will return the
date formatted in a human readable form in American English. In SpiderMonkey, this consists of the
date portion (day, month, and year) followed by the time portion (hours, minutes, seconds, and
time zone). Sometimes it is desirable to obtain a string of the time portion; such a thing can be
accomplished with the toTimeString method.
The toTimeString method is especially useful because compliant engines implementing ECMA-262 may
differ in the string obtained from toString for Date objects, as the format is implementation-
dependent; simple string slicing approaches may not produce consistent results across multiple
engines.
var d = new Date(1993, 6, 28, 14, 39, 7);
println(d.toString()); // prints Wed Jul 28 1993 14:39:07 GMT-0600 (PDT)
println(d.toTimeString()); // prints 14:39:07 GMT-0600 (PDT)
Returns
- String
Human-readable string of the date in local time.
toUTCString( ) : StringConverts a date to a string, using the universal time convention. ...Converts a date to a string, using the universal time convention.
The value returned by toUTCString is a readable string in American English in the UTC time zone.
The format of the return value may vary according to the platform.
var today = new Date();
var UTCstring = today.toUTCString();
// Mon, 03 Jul 2006 21:44:38 GMT
Returns
- String
String of the date in UTC.
Returns the primitive value of a Date object. ...Returns the primitive value of a Date object. Overrides the
Object.prototype.valueOf method.
The valueOf method returns the primitive value of a Date object as a number data type, the
number of milliseconds since midnight 01 January, 1970 UTC.
This method is functionally equivalent to the getTime method.
This method is usually called internally by JavaScript and not explicitly in code.
x = new Date(56, 6, 17);
myVar = x.valueOf(); //assigns -424713600000 to myVar
Returns
- Number
Date represented as milliseconds.
Creates new Date object.
Parameters
- year : Number/String (optional)
Either UNIX timestamp, date string, or year (when month and day parameters also provided):
Integer value representing the number of milliseconds since 1 January 1970 00:00:00 UTC (Unix Epoch).
String value representing a date. The string should be in a format recognized by the parse method (IETF-compliant RFC 1123 timestamps).
Integer value representing the year. For compatibility (in order to avoid the Y2K problem), you should always specify the year in full; use 1998, rather than 98.
- month : Number (optional)
Integer value representing the month, beginning with 0 for January to 11 for December.
- day : Number (optional)
Integer value representing the day of the month (1-31).
- hour : Number (optional)
Integer value representing the hour of the day (0-23).
- minute : Number (optional)
Integer value representing the minute segment (0-59) of a time reading.
- second : Number (optional)
Integer value representing the second segment (0-59) of a time reading.
- millisecond : Number (optional)
Integer value representing the millisecond segment (0-999) of a time reading.
Returns
Returns the day of the month for the specified date according to local time.
The second statement below assigns the value 25 to the variable day, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
day = Xmas95.getDate()
Returns
- Number
Value between 1 and 31.
Returns the day of the week for the specified date according to local time.
The value returned by getDay is an integer corresponding to the day of the week: 0 for Sunday, 1
for Monday, 2 for Tuesday, and so on.
The second statement below assigns the value 1 to weekday, based on the value of the Date
object Xmas95. December 25, 1995, is a Monday.
Xmas95 = new Date("December 25, 1995 23:15:00");
weekday = Xmas95.getDay();
Returns
- Number
A numeric representation of the day from Sunday (0) to Saturday (6).
Returns the year of the specified date according to local time.
The value returned by getFullYear is an absolute number. For dates between the years 1000 and
9999, getFullYear returns a four-digit number, for example, 1995. Use this function to make sure
a year is compliant with years after 2000.
Use this method instead of the getYear method.
The following example assigns the four-digit value of the current year to the variable yr.
var today = new Date();
var yr = today.getFullYear();
Returns
- Number
Four digit representation of the year.
Returns the hour for the specified date according to local time.
The second statement below assigns the value 23 to the variable hours, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
hours = Xmas95.getHours()
Returns
- Number
Value between 0 and 23, using 24-hour clock.
Returns the milliseconds in the specified date according to local time.
The following example assigns the milliseconds portion of the current time to the variable ms.
var ms;
Today = new Date();
ms = Today.getMilliseconds();
Returns
- Number
A number between 0 and 999.
Returns the minutes in the specified date according to local time.
The second statement below assigns the value 15 to the variable minutes, based on the value of
the Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
minutes = Xmas95.getMinutes()
Returns
- Number
Value between 0 and 59.
Returns the month in the specified date according to local time.
The second statement below assigns the value 11 to the variable month, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:00")
month = Xmas95.getMonth()
Returns
- Number
An integer between 0 and 11. 0 corresponds to January, 1 to February, and so on.
Returns the seconds in the specified date according to local time.
The second statement below assigns the value 30 to the variable secs, based on the value of the
Date object Xmas95.
Xmas95 = new Date("December 25, 1995 23:15:30")
secs = Xmas95.getSeconds()
Returns
- Number
Value between 0 and 59.
Returns the numeric value corresponding to the time for the specified date according to universal time.
The value returned by the getTime method is the number of milliseconds since 1 January 1970
00:00:00 UTC. You can use this method to help assign a date and time to another Date object.
This method is functionally equivalent to the valueOf method.
Using getTime for copying dates
Constructing a date object with the identical time value.
var birthday = new Date(1994, 12, 10);
var copy = new Date();
copy.setTime(birthday.getTime());
Measuring execution time
Subtracting two subsequent getTime calls on newly generated Date objects, give the time span between these two calls. This can be used to calculate the executing time of some operations.
var end, start;
start = new Date();
for (var i = 0; i < 1000; i++)
Math.sqrt(i);
end = new Date();
console.log("Operation took " + (end.getTime() - start.getTime()) + " msec");
Returns
- Number
Number of milliseconds since 1/1/1970 (GMT).
Returns the time-zone offset from UTC, in minutes, for the current locale.
The time-zone offset is the difference, in minutes, between UTC and local time. Note that this means that the offset is positive if the local timezone is behind UTC and negative if it is ahead. For example, if your time zone is UTC+10 (Australian Eastern Standard Time), -600 will be returned. Daylight savings time prevents this value from being a constant even for a given locale
x = new Date()
currentTimeZoneOffsetInHours = x.getTimezoneOffset()/60
Returns
- Number
Minutes between GMT and local time.
Returns the day (date) of the month in the specified date according to universal time.
The following example assigns the day portion of the current date to the variable d.
var d;
Today = new Date();
d = Today.getUTCDate();
Returns
- Number
Integer between 1 and 31 representing the day.
Returns the day of the week in the specified date according to universal time.
The following example assigns the weekday portion of the current date to the variable weekday.
var weekday;
Today = new Date()
weekday = Today.getUTCDay()
Returns
- Number
A numeric representation of the day from Sunday (0) to Saturday (6).
Returns the year in the specified date according to universal time.
The following example assigns the four-digit value of the current year to the variable yr.
var yr;
Today = new Date();
yr = Today.getUTCFullYear();
Returns
- Number
Four digit representation of the year.
Returns the hours in the specified date according to universal time.
The following example assigns the hours portion of the current time to the variable hrs.
var hrs;
Today = new Date();
hrs = Today.getUTCHours();
Returns
- Number
Value between 0 and 23.
Returns the milliseconds in the specified date according to universal time.
The following example assigns the milliseconds portion of the current time to the variable ms.
var ms;
Today = new Date();
ms = Today.getUTCMilliseconds();
Returns
- Number
Milliseconds portion of the Date.
Returns the minutes in the specified date according to universal time.
The following example assigns the minutes portion of the current time to the variable min.
var min;
Today = new Date();
min = Today.getUTCMinutes();
Returns
- Number
Value between 0 and 59.
Returns the month of the specified date according to universal time.
The following example assigns the month portion of the current date to the variable mon.
var mon;
Today = new Date();
mon = Today.getUTCMonth();
Returns
- Number
Value between 0 (January) and 11 (December).
Returns the seconds in the specified date according to universal time.
The following example assigns the seconds portion of the current time to the variable sec.
var sec;
Today = new Date();
sec = Today.getUTCSeconds();
Returns
- Number
Value between 0 and 59.
Sets the day of the month (1-31) for a specified date according to local time.
If the parameter you specify is outside of the expected range, setDate attempts to update the
date information in the Date object accordingly. For example, if you use 0 for dayValue, the
date will be set to the last day of the previous month.
The second statement below changes the day for theBigDay to July 24 from its original value.
theBigDay = new Date("July 27, 1962 23:30:00")
theBigDay.setDate(24)
Parameters
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the full year (4 digits for 4-digit years) for a specified date according to local time.
If you do not specify the monthValue and dayValue parameters, the values returned from the
getMonth and getDate methods are used.
If a parameter you specify is outside of the expected range, setFullYear attempts to update the
other parameters and the date information in the Date object accordingly. For example, if you
specify 15 for monthValue, the year is incremented by 1 (year + 1), and 3 is used for the month.
theBigDay = new Date(); theBigDay.setFullYear(1997);
Parameters
- yearValue : Number
An integer specifying the numeric value of the year, for example, 1995.
- monthValue : Number
An integer between 0 and 11 representing the months January through December.
- dayValue : Number
An integer between 1 and 31 representing the day of the month. If you specify the
dayValueparameter, you must also specify themonthValue.
Returns
- Number
New date represented as milliseconds.
Sets the hours (0-23) for a specified date according to local time.
If you do not specify the minutesValue, secondsValue, and msValue parameters, the values
returned from the getUTCMinutes, getUTCSeconds, and getMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setHours attempts to update the date
information in the Date object accordingly. For example, if you use 100 for secondsValue, the
minutes will be incremented by 1 (min + 1), and 40 will be used for seconds.
theBigDay.setHours(7)
Parameters
- hoursValue : Number
An integer between 0 and 23, representing the hour.
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the
secondsValueparameter, you must also specify theminutesValue. - msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValueparameter, you must also specify theminutesValueandsecondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the milliseconds (0-999) for a specified date according to local time.
If you specify a number outside the expected range, the date information in the Date object is
updated accordingly. For example, if you specify 1005, the number of seconds is incremented by 1,
and 5 is used for the milliseconds.
theBigDay = new Date();
theBigDay.setMilliseconds(100);
Parameters
- millisecondsValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
Sets the minutes (0-59) for a specified date according to local time.
If you do not specify the secondsValue and msValue parameters, the values returned from
getSeconds and getMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setMinutes attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes (minutesValue) will be incremented by 1 (minutesValue + 1), and 40 will be used for
seconds.
theBigDay.setMinutes(45)
Parameters
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the secondsValue parameter, you must also specify the
minutesValue. - msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValueparameter, you must also specify theminutesValueandsecondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the month (0-11) for a specified date according to local time.
If you do not specify the dayValue parameter, the value returned from the getDate method is
used.
If a parameter you specify is outside of the expected range, setMonth attempts to update the date
information in the Date object accordingly. For example, if you use 15 for monthValue, the year
will be incremented by 1 (year + 1), and 3 will be used for month.
theBigDay.setMonth(6)
Parameters
- monthValue : Number
An integer between 0 and 11 (representing the months January through December).
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the seconds (0-59) for a specified date according to local time.
If you do not specify the msValue parameter, the value returned from the getMilliseconds method
is used.
If a parameter you specify is outside of the expected range, setSeconds attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes stored in the Date object will be incremented by 1, and 40 will be used for seconds.
theBigDay.setSeconds(30)
Parameters
- secondsValue : Number
An integer between 0 and 59.
- msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValueparameter, you must also specify theminutesValueandsecondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the Date object to the time represented by a number of milliseconds since January 1, 1970, 00:00:00 UTC, allowing for negative numbers for times prior.
Use the setTime method to help assign a date and time to another Date object.
theBigDay = new Date("July 1, 1999")
sameAsBigDay = new Date()
sameAsBigDay.setTime(theBigDay.getTime())
Parameters
- timeValue : Number
An integer representing the number of milliseconds since 1 January 1970, 00:00:00 UTC.
Returns
- Number
New date represented as milliseconds.
Sets the day of the month (1-31) for a specified date according to universal time.
If a parameter you specify is outside of the expected range, setUTCDate attempts to update the
date information in the Date object accordingly. For example, if you use 40 for dayValue, and
the month stored in the Date object is June, the day will be changed to 10 and the month will be
incremented to July.
theBigDay = new Date();
theBigDay.setUTCDate(20);
Parameters
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the full year (4 digits for 4-digit years) for a specified date according to universal time.
If you do not specify the monthValue and dayValue parameters, the values returned from the
getMonth and getDate methods are used.
If a parameter you specify is outside of the expected range, setUTCFullYear attempts to update
the other parameters and the date information in the Date object accordingly. For example, if you
specify 15 for monthValue, the year is incremented by 1 (year + 1), and 3 is used for the month.
theBigDay = new Date();
theBigDay.setUTCFullYear(1997);
Parameters
- yearValue : Number
An integer specifying the numeric value of the year, for example, 1995.
- monthValue : Number
An integer between 0 and 11 representing the months January through December.
- dayValue : Number
An integer between 1 and 31 representing the day of the month. If you specify the
dayValueparameter, you must also specify themonthValue.
Returns
- Number
New date represented as milliseconds.
Sets the hour (0-23) for a specified date according to universal time.
If you do not specify the minutesValue, secondsValue, and msValue parameters, the values
returned from the getUTCMinutes, getUTCSeconds, and getUTCMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setUTCHours attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes will be incremented by 1 (min + 1), and 40 will be used for seconds.
theBigDay = new Date();
theBigDay.setUTCHours(8);
Parameters
- hoursValue : Number
An integer between 0 and 23, representing the hour.
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the
secondsValueparameter, you must also specify theminutesValue. - msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValueparameter, you must also specify theminutesValueandsecondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the milliseconds (0-999) for a specified date according to universal time.
If a parameter you specify is outside of the expected range, setUTCMilliseconds attempts to
update the date information in the Date object accordingly. For example, if you use 1100 for
millisecondsValue, the seconds stored in the Date object will be incremented by 1, and 100 will
be used for milliseconds.
theBigDay = new Date();
theBigDay.setUTCMilliseconds(500);
Parameters
- millisecondsValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
Sets the minutes (0-59) for a specified date according to universal time.
If you do not specify the secondsValue and msValue parameters, the values returned from
getUTCSeconds and getUTCMilliseconds methods are used.
If a parameter you specify is outside of the expected range, setUTCMinutes attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes (minutesValue) will be incremented by 1 (minutesValue + 1), and 40 will be used for
seconds.
theBigDay = new Date();
theBigDay.setUTCMinutes(43);
Parameters
- minutesValue : Number
An integer between 0 and 59, representing the minutes.
- secondsValue : Number
An integer between 0 and 59, representing the seconds. If you specify the
secondsValueparameter, you must also specify theminutesValue. - msValue : Number
A number between 0 and 999, representing the milliseconds. If you specify the
msValueparameter, you must also specify theminutesValueandsecondsValue.
Returns
- Number
New date represented as milliseconds.
Sets the month (0-11) for a specified date according to universal time.
If you do not specify the dayValue parameter, the value returned from the getUTCDate method is
used.
If a parameter you specify is outside of the expected range, setUTCMonth attempts to update the
date information in the Date object accordingly. For example, if you use 15 for monthValue, the
year will be incremented by 1 (year + 1), and 3 will be used for month.
theBigDay = new Date();
theBigDay.setUTCMonth(11);
Parameters
- monthValue : Number
An integer between 0 and 11, representing the months January through December.
- dayValue : Number
An integer from 1 to 31, representing the day of the month.
Returns
- Number
New date represented as milliseconds.
Sets the seconds (0-59) for a specified date according to universal time.
If you do not specify the msValue parameter, the value returned from the getUTCMilliseconds
methods is used.
If a parameter you specify is outside of the expected range, setUTCSeconds attempts to update the
date information in the Date object accordingly. For example, if you use 100 for secondsValue,
the minutes stored in the Date object will be incremented by 1, and 40 will be used for seconds.
theBigDay = new Date();
theBigDay.setUTCSeconds(20);
Parameters
- secondsValue : Number
An integer between 0 and 59.
- msValue : Number
A number between 0 and 999, representing the milliseconds.
Returns
- Number
New date represented as milliseconds.
Returns the "date" portion of the Date as a human-readable string in American English.
Date instances refer to a specific point in time. Calling toString will return the
date formatted in a human readable form in American English. In SpiderMonkey, this consists of the
date portion (day, month, and year) followed by the time portion (hours, minutes, seconds, and time
zone). Sometimes it is desirable to obtain a string of the date portion; such a thing can be
accomplished with the toDateString method.
The toDateString method is especially useful because compliant engines implementing ECMA-262 may
differ in the string obtained from toString for Date objects, as the format is implementation-
dependent and simple string slicing approaches may not produce consistent results across multiple
engines.
var d = new Date(1993, 6, 28, 14, 39, 7);
println(d.toString()); // prints Wed Jul 28 1993 14:39:07 GMT-0600 (PDT)
println(d.toDateString()); // prints Wed Jul 28 1993
Returns
- String
Human-readable string, in local time.
Returns a JSON representation of the Date object.
Date instances refer to a specific point in time. Calling toJSON()
returns a JSON formatted string representing the Date object's
value. This method is generally intended to, by default, usefully
serialize Date objects during JSON serialization.
var jsonDate = (new Date()).toJSON();
var backToDate = new Date(jsonDate);
console.log("Serialized date object: " + jsonDate);
// Serialized date object: 2013-01-17T12:59:08.449Z
NOTE: This method is part of the ECMAScript 5 standard.
Returns
- String
Date value in
YYYY-MM-DDTHH-MM-SS.MMMZformat.
Returns the "date" portion of the Date as a string, using the current locale's conventions.
The toLocaleDateString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98). If the operating system is not
year-2000 compliant and does not use the full year for years before 1900 or over 2000,
toLocaleDateString returns a string that is not year-2000 compliant. toLocaleDateString behaves
similarly to toString when converting a year that the operating system does not properly format.
Methods such as getDate, getMonth, and getFullYear give more portable results than
toLocaleDateString. Use toLocaleDateString when the intent is to display to the user a string
formatted using the regional format chosen by the user. Be aware that this method, due to its
nature, behaves differently depending on the operating system and on the user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35) //months are represented by 0 to 11
today.toLocaleDateString()
In this example, toLocaleDateString returns a string value that is similar to the following form.
The exact format depends on the platform, locale and user's settings.
12/18/95
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleDateString(); // Good example
"Last visit was at " + someDate.toLocaleDateString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending on the country.
Converts a date to a string, using the current locale's conventions. Overrides
the Object.toLocaleString method.
The toLocaleString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98). If the operating system is not
year-2000 compliant and does not use the full year for years before 1900 or over 2000,
toLocaleString returns a string that is not year-2000 compliant. toLocaleString behaves
similarly to toString when converting a year that the operating system does not properly format.
Methods such as getDate, getMonth, getFullYear, getHours, getMinutes, and getSeconds
give more portable results than toLocaleString. Use toLocaleString when the intent is to
display to the user a string formatted using the regional format chosen by the user. Be aware that
this method, due to its nature, behaves differently depending on the operating system and on the
user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35); //months are represented by 0 to 11
today.toLocaleString();
In this example, toLocaleString returns a string value that is similar to the following form. The
exact format depends on the platform, locale and user's settings.
12/18/95 17:28:35
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleString(); // Good example
"Last visit was at " + someDate.toLocaleString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending on the country.
Returns the "time" portion of the Date as a string, using the current locale's conventions.
The toLocaleTimeString method relies on the underlying operating system in formatting dates. It
converts the date to a string using the formatting convention of the operating system where the
script is running. For example, in the United States, the month appears before the date (04/15/98),
whereas in Germany the date appears before the month (15.04.98).
Methods such as getHours, getMinutes, and getSeconds give more consistent results than
toLocaleTimeString. Use toLocaleTimeString when the intent is to display to the user a string
formatted using the regional format chosen by the user. Be aware that this method, due to its
nature, behaves differently depending on the operating system and on the user's settings.
In the following example, today is a Date object:
today = new Date(95,11,18,17,28,35) //months are represented by 0 to 11
today.toLocaleTimeString()
In this example, toLocaleTimeString returns a string value that is similar to the following form.
The exact format depends on the platform.
17:28:35
You shouldn't use this method in contexts where you rely on a particular format or locale.
"Last visit: " + someDate.toLocaleTimeString(); // Good example
"Last visit was at " + someDate.toLocaleTimeString(); // Bad example
Returns
- String
Human-readable string that may be formatted differently depending on the country.
Returns a string representing the specified Date object. Overrides the
Object.prototype.toString method.
The Date object overrides the toString method of the Object object; it does not inherit
Object.toString. For Date objects, the toString method returns a string representation of the
object.
toString always returns a string representation of the date in American English.
JavaScript calls the toString method automatically when a date is to be represented as a text
value or when a date is referred to in a string concatenation.
The following assigns the toString value of a Date object to myVar:
x = new Date();
myVar=x.toString(); //assigns a value to myVar similar to:
//Mon Sep 28 1998 14:36:22 GMT-0700 (Pacific Daylight Time)
Returns
- String
Human-readable string of the date in local time.
Returns the "time" portion of the Date as a human-readable string.
Date instances refer to a specific point in time. Calling toString will return the
date formatted in a human readable form in American English. In SpiderMonkey, this consists of the
date portion (day, month, and year) followed by the time portion (hours, minutes, seconds, and
time zone). Sometimes it is desirable to obtain a string of the time portion; such a thing can be
accomplished with the toTimeString method.
The toTimeString method is especially useful because compliant engines implementing ECMA-262 may
differ in the string obtained from toString for Date objects, as the format is implementation-
dependent; simple string slicing approaches may not produce consistent results across multiple
engines.
var d = new Date(1993, 6, 28, 14, 39, 7);
println(d.toString()); // prints Wed Jul 28 1993 14:39:07 GMT-0600 (PDT)
println(d.toTimeString()); // prints 14:39:07 GMT-0600 (PDT)
Returns
- String
Human-readable string of the date in local time.
Converts a date to a string, using the universal time convention.
The value returned by toUTCString is a readable string in American English in the UTC time zone.
The format of the return value may vary according to the platform.
var today = new Date();
var UTCstring = today.toUTCString();
// Mon, 03 Jul 2006 21:44:38 GMT
Returns
- String
String of the date in UTC.
Returns the primitive value of a Date object. Overrides the Object.prototype.valueOf method.
The valueOf method returns the primitive value of a Date object as a number data type, the
number of milliseconds since midnight 01 January, 1970 UTC.
This method is functionally equivalent to the getTime method.
This method is usually called internally by JavaScript and not explicitly in code.
x = new Date(56, 6, 17);
myVar = x.valueOf(); //assigns -424713600000 to myVar
Returns
- Number
Date represented as milliseconds.
Static methods Accepts the same parameters as the longest form of the constructor, and returns
the number of milliseconds in a Date ...Accepts the same parameters as the longest form of the constructor, and returns
the number of milliseconds in a Date object since January 1, 1970, 00:00:00,
universal time.
UTC takes comma-delimited date parameters and returns the number of milliseconds between January
1, 1970, 00:00:00, universal time and the time you specified.
You should specify a full year for the year; for example, 1998. If a year between 0 and 99 is
specified, the method converts the year to a year in the 20th century (1900 + year); for example,
if you specify 95, the year 1995 is used.
The UTC method differs from the Date constructor in two ways.
* Date.UTC uses universal time instead of the local time.
* Date.UTC returns a time value as a number instead of creating a Date object.
If a parameter you specify is outside of the expected range, the UTC method updates the other
parameters to allow for your number. For example, if you use 15 for month, the year will be
incremented by 1 (year + 1), and 3 will be used for the month.
Because UTC is a static method of Date, you always use it as Date.UTC(), rather than as a
method of a Date object you created.
The following statement creates a Date object using GMT instead of local time:
gmtDate = new Date(Date.UTC(96, 11, 1, 0, 0, 0));
Parameters
- year : Number
A year after 1900.
- month : Number
An integer between 0 and 11 representing the month.
- date : Number
An integer between 1 and 31 representing the day of the month.
- hrs : Number
An integer between 0 and 23 representing the hours.
- min : Number
An integer between 0 and 59 representing the minutes.
- sec : Number
An integer between 0 and 59 representing the seconds.
- ms : Number
An integer between 0 and 999 representing the milliseconds.
Returns
- Number
Number of milliseconds since January 1, 1970, 00:00:00, universal time.
Returns the numeric value corresponding to the current time. ...Returns the numeric value corresponding to the current time.
The now method returns the milliseconds elapsed since 1 January 1970 00:00:00 UTC up until now as
a number.
When using now to create timestamps or unique IDs, keep in mind that the resolution may be 15
milliseconds on Windows, so you could end up with several equal values if now is called multiple
times within a short time span.
Returns
- Number
Returns the number of milliseconds elapsed since 1 January 1970 00:00:00 UTC.
Parses a string representation of a date, and returns the number of milliseconds
since January 1, 1970, 00:00:00, loc...Parses a string representation of a date, and returns the number of milliseconds
since January 1, 1970, 00:00:00, local time.
The parse method takes a date string (such as "Dec 25, 1995") and returns the number of
milliseconds since January 1, 1970, 00:00:00 UTC. The local time zone is used to interpret
arguments that do not contain time zone information. This function is useful for setting date
values based on string values, for example in conjunction with the setTime method and the
Date object.
Given a string representing a time, parse returns the time value. It accepts the IETF standard (RFC
1123 Section 5.2.14 and elsewhere) date syntax: "Mon, 25 Dec 1995 13:30:00 GMT". It understands
the continental US time-zone abbreviations, but for general use, use a time-zone offset, for
example, "Mon, 25 Dec 1995 13:30:00 GMT+0430" (4 hours, 30 minutes east of the Greenwich
meridian). If you do not specify a time zone, the local time zone is assumed. GMT and UTC are
considered equivalent.
Using parse
If IPOdate is an existing Date object, then you can set it to August 9, 1995 (local time) as
follows:
IPOdate.setTime(Date.parse("Aug 9, 1995"));
Some other examples:
// Returns 807937200000 in time zone GMT-0300, and other values in other
// timezones, since the argument does not specify a time zone.
Date.parse("Aug 9, 1995");
// Returns 807926400000 no matter the local time zone.
Date.parse("Wed, 09 Aug 1995 00:00:00 GMT");
// Returns 807937200000 in timezone GMT-0300, and other values in other
// timezones, since there is no time zone specifier in the argument.
Date.parse("Wed, 09 Aug 1995 00:00:00");
// Returns 0 no matter the local time zone.
Date.parse("Thu, 01 Jan 1970 00:00:00 GMT");
// Returns 14400000 in timezone GMT-0400, and other values in other
// timezones, since there is no time zone specifier in the argument.
Date.parse("Thu, 01 Jan 1970 00:00:00");
// Returns 14400000 no matter the local time zone.
Date.parse("Thu, 01 Jan 1970 00:00:00 GMT-0400");
Parameters
- dateString : String
A string representing a date.
Returns
- Number
Number of milliseconds since January 1, 1970, 00:00:00, local time.
Accepts the same parameters as the longest form of the constructor, and returns
the number of milliseconds in a Date object since January 1, 1970, 00:00:00,
universal time.
UTC takes comma-delimited date parameters and returns the number of milliseconds between January
1, 1970, 00:00:00, universal time and the time you specified.
You should specify a full year for the year; for example, 1998. If a year between 0 and 99 is specified, the method converts the year to a year in the 20th century (1900 + year); for example, if you specify 95, the year 1995 is used.
The UTC method differs from the Date constructor in two ways.
* Date.UTC uses universal time instead of the local time.
* Date.UTC returns a time value as a number instead of creating a Date object.
If a parameter you specify is outside of the expected range, the UTC method updates the other
parameters to allow for your number. For example, if you use 15 for month, the year will be
incremented by 1 (year + 1), and 3 will be used for the month.
Because UTC is a static method of Date, you always use it as Date.UTC(), rather than as a
method of a Date object you created.
The following statement creates a Date object using GMT instead of local time:
gmtDate = new Date(Date.UTC(96, 11, 1, 0, 0, 0));
Parameters
- year : Number
A year after 1900.
- month : Number
An integer between 0 and 11 representing the month.
- date : Number
An integer between 1 and 31 representing the day of the month.
- hrs : Number
An integer between 0 and 23 representing the hours.
- min : Number
An integer between 0 and 59 representing the minutes.
- sec : Number
An integer between 0 and 59 representing the seconds.
- ms : Number
An integer between 0 and 999 representing the milliseconds.
Returns
- Number
Number of milliseconds since January 1, 1970, 00:00:00, universal time.
Returns the numeric value corresponding to the current time.
The now method returns the milliseconds elapsed since 1 January 1970 00:00:00 UTC up until now as
a number.
When using now to create timestamps or unique IDs, keep in mind that the resolution may be 15
milliseconds on Windows, so you could end up with several equal values if now is called multiple
times within a short time span.
Returns
- Number
Returns the number of milliseconds elapsed since 1 January 1970 00:00:00 UTC.
Parses a string representation of a date, and returns the number of milliseconds since January 1, 1970, 00:00:00, local time.
The parse method takes a date string (such as "Dec 25, 1995") and returns the number of
milliseconds since January 1, 1970, 00:00:00 UTC. The local time zone is used to interpret
arguments that do not contain time zone information. This function is useful for setting date
values based on string values, for example in conjunction with the setTime method and the
Date object.
Given a string representing a time, parse returns the time value. It accepts the IETF standard (RFC
1123 Section 5.2.14 and elsewhere) date syntax: "Mon, 25 Dec 1995 13:30:00 GMT". It understands
the continental US time-zone abbreviations, but for general use, use a time-zone offset, for
example, "Mon, 25 Dec 1995 13:30:00 GMT+0430" (4 hours, 30 minutes east of the Greenwich
meridian). If you do not specify a time zone, the local time zone is assumed. GMT and UTC are
considered equivalent.
Using parse
If IPOdate is an existing Date object, then you can set it to August 9, 1995 (local time) as
follows:
IPOdate.setTime(Date.parse("Aug 9, 1995"));
Some other examples:
// Returns 807937200000 in time zone GMT-0300, and other values in other
// timezones, since the argument does not specify a time zone.
Date.parse("Aug 9, 1995");
// Returns 807926400000 no matter the local time zone.
Date.parse("Wed, 09 Aug 1995 00:00:00 GMT");
// Returns 807937200000 in timezone GMT-0300, and other values in other
// timezones, since there is no time zone specifier in the argument.
Date.parse("Wed, 09 Aug 1995 00:00:00");
// Returns 0 no matter the local time zone.
Date.parse("Thu, 01 Jan 1970 00:00:00 GMT");
// Returns 14400000 in timezone GMT-0400, and other values in other
// timezones, since there is no time zone specifier in the argument.
Date.parse("Thu, 01 Jan 1970 00:00:00");
// Returns 14400000 no matter the local time zone.
Date.parse("Thu, 01 Jan 1970 00:00:00 GMT-0400");
Parameters
- dateString : String
A string representing a date.
Returns
- Number
Number of milliseconds since January 1, 1970, 00:00:00, local time.