JavaScript Date Common point of knowledge

1. New Date (DATESTR): Converts a string to a Date objectParameters:
①datestr {string}: A string that can be converted to a Date object (can be omitted); There are two main types of strings:
1) yyyy/mm/dd HH:mm:ss: If the time is omitted, the time of the date object returned is 00:00:00.
2) Yyyy-mm-dd HH:mm:ss: If the time is omitted, the Date object returned is 08:00:00 (plus the local time zone). If you do not omit the time, this string will fail in IE conversion!
return value:

{Date} returns a converted Date object.

Example:

var dt = new Date (' 2014/12/25 '); YYYY/MM/DD
console.log (DT);//=> {DATE}:2014/12/25 00:00:00
dt = new Date (' 2014/12/25 12:00:00 ');//yyyy/ Mm/dd HH:mm:ss
console.log (DT);//=> {DATE}:2014/12/25 12:00:00
 
dt = new Date (' 2014-12-25 ');//yyyy-mm-dd< C4/>console.log (DT); => {date}:2014-12-25 08:00:00 (plus the time zone of East 8)
dt = new Date (' 2014-12-25 12:00:00 ');//Yyyy-mm-dd HH:mm:ss (Note: This conversion There will be an error in IE. )
console.log (DT);//=> {date}:2014-12-25 12:00:00

2, Get method

getFullYear (): Returns the year value of the Date object; 4-bit year.
GetMonth (): Returns the month value of the Date object. Starting from 0, so the real month = Returns the value +1.
GetDate (): Returns the date value in the month of the Date object, 1~31 the range of the value.
GetHours (): Returns a Date object's small value.
Getminutes (): Returns the minute value of a Date object.
Getseconds (): Returns the number of seconds for a Date object.
Getmilliseconds (): Returns the millisecond value of the Date object.
Getday (): Returns the week value of the week for the date object, 0 for Sunday, 1 for Monday, 2 for Tuesday, and so on
GetTime (): Returns the millisecond value between the Date object and ' 1970/01/01 00:00:00 ' (The time zone in Beijing is East 8, and the starting time is actually: ' 1970/01/01 08:00:00 '). 3. Set Method

setFullYear (year, Opt_month, opt_date): Sets the Date object's age value, 4-bit year.
Setmonth (Month, opt_date): Sets the month value of the Date object. 0 indicates January, 11 represents December.
Setdate (date): Sets the date value in the month of the date object; 1~31 the range of the value.
Sethours (Hour, opt_min, Opt_sec, opt_msec): Sets the Date object's small values.
Setminutes (Min, Opt_sec, opt_msec): Sets the minute value of the Date object.
Setseconds (sec, opt_msec): Sets the number of seconds for a Date object.
Setmilliseconds (msec): Sets the millisecond value of the Date object.

var dt = new Date ();
Dt.setfullyear (2014); => 2014: Year
dt.setmonth (one);//=> 11: Month; actual for December (month starting from 0)
dt.setdate;//=> 25: Day
dt.sethours (15); => 15:
dt.setminutes//=> 30: Min
dt.setseconds (s);//=> 40: Sec
dt.setmilliseconds (333); => 333: Millisecond
console.log (DT);//=>  December 25, 2014 15:30 40 second 333 ms

4, Date.parse (DATESTR)

Description: Converts a string to a Date object and returns the millisecond value between this Date object and ' 1970/01/01 00:00:00 ' (The time zone in Beijing is East 8, and the starting time is actually: ' 1970/01/01 08:00:00 ')
Parameters:
①datestr {string}: A string that can be converted to a Date object (can be omitted); There are two main types of strings:
1) yyyy/mm/dd HH:mm:ss: If the time is omitted, the time of the date object returned is 00:00:00.
2) Yyyy-mm-dd HH:mm:ss: If the time is omitted, the Date object returned is 08:00:00 (plus the local time zone). If you do not omit the time, this string returns Nan (not a number) in IE!
return value:
{int} returns the number of milliseconds between the converted Date object and the start time.
5, new Date (year, month, Opt_day, Opt_hours, Opt_minutes, Opt_seconds, Opt_milliseconds)

Convert Date To Date object
Parameters:
①year {int}: year; 4 digits. such as: 1999, 2014
②month {int}: month; 2 digits. Starting from 0, 0 means January, 11 represents December.
③opt_day {int} is optional: number, 2 digits, starting from 1, 1 represents 1th.
④opt_hours {int} optional: time; 2 digits; Value 0~23.
⑤opt_minutes {int} optional: 2 digits; 0~59.
⑥opt_seconds {int} optional: seconds; 2 not digits; 0~59 value.
⑦opt_milliseconds {int} is optional: milliseconds; 0~999 value.
return value:
{Date} returns a converted Date object.

var dt = new Date (2014, 11); December 2014 (The number of months entered here is one)
console.log (DT);//=> {date}:2014/12/01 00:00:00
dt = new Date (2014, 11, 25);//201 4 year December 25
console.log (DT);//=> {DATE}:2014/12/25 00:00:00
dt = new Date (2014, 11, 25, 15, 30, 40);//December 2014 25th 15:30 40 seconds
console.log (DT);//=> {DATE}:2014/12/25 15:30:40
dt = new Date (2014, 12, 25);//March 25, 2014 (This is lost The number of months entered is 12, which represents the 13th month, and jumps to the second year of January)
console.log (DT);//=> {DATE}:2015/01/25