Core object | |
Implemented in |
Navigator 2.0, LiveWire 1.0 Navigator 3.0: added prototype property
|
Created by
The Date
constructor:
new Date()
new Date("month day, year hours:minutes:seconds")
new Date(yr_num, mo_num, day_num)
new Date(yr_num, mo_num, day_num, hr_num, min_num, sec_num) Parameters
Description
If you supply no arguments, the constructor creates a Date
object for today's date and 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, and seconds.
The way JavaScript handles dates is very similar to the way Java handles dates: both languages have many of the same date methods, and both store dates internally as the number of milliseconds since January 1, 1970 00:00:00. Dates prior to 1970 are not allowed.
Property Summary
|
Allows the addition of properties to a Date object.
|
Examples
The following examples show several ways to assign dates:
today = new Date()
birthday = new Date("December 17, 1995 03:24:00")
birthday = new Date(95,11,17)
birthday = new Date(95,11,17,3,24,0) Properties
prototype
Represents the prototype for this class. You can use the prototype to add properties or methods to all instances of a class. For information on prototypes, see Function.prototype
.
Property of |
Date
|
Implemented in | Navigator 3.0, LiveWire 1.0 |
Methods
getDate
Returns the day of the month for the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getDate()
Parameters
None
Description
The value returned by getDate
is an integer between 1 and 31.
Examples
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() See also
Date.setDate
getDay
Returns the day of the week for the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getDay()
Parameters
None
Description
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.
Examples
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()getHours
Returns the hour for the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getHours()
Parameters
None
Description
The value returned by getHours
is an integer between 0 and 23.
Examples
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() See also
Date.setHours
getMinutes
Returns the minutes in the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getMinutes()
Parameters
None
Description
The value returned by getMinutes
is an integer between 0 and 59.
Examples
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() See also
Date.setMinutes
getMonth
Returns the month in the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getMonth()
Parameters
None
Description
The value returned by getMonth
is an integer between 0 and 11. 0 corresponds to January, 1 to February, and so on.
Examples
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() See also
Date.setMonth
getSeconds
Returns the seconds in the current time.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getSeconds()
Parameters
None
Description
The value returned by getSeconds
is an integer between 0 and 59.
Examples
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() See also
Date.setSeconds
getTime
Returns the numeric value corresponding to the time for the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getTime()
Parameters
None
Description
The value returned by the getTime
method is the number of milliseconds since 1 January 1970 00:00:00. You can use this method to help assign a date and time to another Date
object.
Examples
The following example assigns the date value of theBigDay
to sameAsBigDay
:
theBigDay = new Date("July 1, 1999")
sameAsBigDay = new Date()
sameAsBigDay.setTime(theBigDay.getTime()) See also
Date.setTime
getTimezoneOffset
Returns the time-zone offset in minutes for the current locale.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getTimezoneOffset()
Parameters
None
Description
The time-zone offset is the difference between local time and Greenwich Mean Time (GMT). Daylight savings time prevents this value from being a constant.
Examples
x = new Date()
currentTimeZoneOffsetInHours = x.getTimezoneOffset()/60getYear
Returns the year in the specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
getYear()
Parameters
None
Description
The getYear
method returns either a 2-digit or 4-digit year:
year
.
Xmas = new Date("December 25, 1995 23:15:00")Example 2. The second statement assigns the value 2000 to the variable
year = Xmas.getYear()
year
.
Xmas = new Date("December 25, 2000 23:15:00")Example 3. The second statement assigns the value 95 to the variable
year = Xmas.getYear()
year
, representing the year 1995.
Xmas.setYear(95)
year = Xmas.getYear()
Date.setYear
parse
Returns the number of milliseconds in a date string since January 1, 1970, 00:00:00, local time.
Method of |
Date
|
Static | |
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
Date.parse(dateString)
Parameters
:
dateString | A string representing a date. |
Description
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 (local time). 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 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 west of the Greenwich meridian). If you do not specify a time zone, the local time zone is assumed. GMT and UTC are considered equivalent.
Because parse
is a static method of Date
, you always use it as Date.parse()
, rather than as a method of a Date
object you created.
Examples
If IPOdate
is an existing Date
object, then you can set it to August 9, 1995 as follows:
IPOdate.setTime(Date.parse("Aug 9, 1995"))
See also
Date.UTC
setDate
Sets the day of the month for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setDate(dayValue)
Parameters
dayValue | An integer from 1 to 31, representing the day of the month. |
Examples
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) See also
Date.getDate
setHours
Sets the hours for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setHours(hoursValue)
Parameters
hoursValue | An integer between 0 and 23, representing the hour. |
Examples
theBigDay.setHours(7)
See also
Date.getHours
setMinutes
Sets the minutes for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setMinutes(minutesValue)
Parameters
minutesValue | An integer between 0 and 59, representing the minutes. |
Examples
theBigDay.setMinutes(45)
See also
Date.getMinutes
setMonth
Sets the month for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setMonth(monthValue)
Parameters
monthValue | An integer between 0 and 11 (representing the months January through December). |
Examples
theBigDay.setMonth(6)
See also
Date.getMonth
setSeconds
Sets the seconds for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setSeconds(secondsValue)
Parameters
secondsValue | An integer between 0 and 59. |
Examples
theBigDay.setSeconds(30)
See also
Date.getSeconds
setTime
Sets the value of a Date
object.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setTime(timevalue)
Parameters
timevalue | An integer representing the number of milliseconds since 1 January 1970 00:00:00. |
Description
Use the setTime
method to help assign a date and time to another Date
object.
Examples
theBigDay = new Date("July 1, 1999")
sameAsBigDay = new Date()
sameAsBigDay.setTime(theBigDay.getTime()) See also
Date.getTime
setYear
Sets the year for a specified date.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
setYear(yearValue)
Parameters
yearValue | An integer. |
Description
If yearValue
is a number between 0 and 99 (inclusive), then the year for dateObjectName
is set to 1900 + yearValue
. Otherwise, the year for dateObjectName
is set to yearValue
.
Examples
Note that there are two ways to set years in the 20th century.
Example 1. The year is set to 1996.
theBigDay.setYear(96)
Example 2. The year is set to 1996.
theBigDay.setYear(1996)
Example 3. The year is set to 2000.
theBigDay.setYear(2000)
See also
Date.getYear
toGMTString
Converts a date to a string, using the Internet GMT conventions.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
toGMTString()
Parameters
None
Description
The exact format of the value returned by toGMTString
varies according to the platform.
Examples
In the following example, today
is a Date
object:
today.toGMTString()
In this example, the toGMTString
method converts the date to GMT (UTC) using the operating system's time-zone offset and returns a string value that is similar to the following form. The exact format depends on the platform.
Mon, 18 Dec 1995 17:28:35 GMT
See also
Date.toLocaleString
toLocaleString
Converts a date to a string, using the current locale's conventions.
Method of |
Date
|
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
toLocaleString()
Parameters
None
Description
If you pass a date using toLocaleString
, be aware that different platforms assemble the string in different ways. Using methods such as getHours
, getMinutes
, and getSeconds
gives more portable results.
Examples
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
In this example,
today.toLocaleString()toLocaleString
returns a string value that is similar to the following form. The exact format depends on the platform.
12/18/95 17:28:35
See also
Date.toGMTString
UTC
Returns the number of milliseconds in a Date
object since January 1, 1970, 00:00:00, Universal Coordinated Time (GMT).
Method of |
Date
|
Static | |
Implemented in | Navigator 2.0, LiveWire 1.0 |
Syntax
Date.UTC(year, month, day, hrs, min, sec)
Parameters
Description
UTC
takes comma-delimited date parameters and returns the number of milliseconds since January 1, 1970, 00:00:00, Universal Coordinated Time (GMT).
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.
Examples
The following statement creates a Date
object using GMT instead of local time:
gmtDate = new Date(Date.UTC(96, 11, 1, 0, 0, 0))
See also
Date.parse
Last Updated: 10/31/97 16:00:33