The use of Date objects in JS

A: What is the Date object?

The Date object is used to process dates and times.

Two: Date creation syntax

1. Direct access to the current time is standard Time

var date = new Date ()

Console.log (date)//tue Dec 23:09:42 gmt+0800 (China Standard Time)

Note: The Date object automatically saves the current date and time as its initial value.

2. Specify time to change to standard time

var date1 = new Date ("January 12,2006 22:19:35")

Console.log (date1)//thu Jan 2006 22:19:35 gmt+0800 (China Standard Time)

Several of the following formats are available:

New Date ("Month dd,yyyy hh:mm:ss");
New Date ("Month dd,yyyy");
New Date (YYYY,MTH,DD,HH,MM,SS);
New Date (YYYY,MTH,DD);
New Date (MS);

Three: Common Object methods

Date.getfullyear ()//2017 returns the year as a four-digit number from a Date object

Date.getmonth ()//11 returns the month from the Date object (0 ~ 11)

Date.getday ()//2 returns one day of the week from a Date object (0 ~ 6)

Date.getdate ()//12 returns one day in one months from a Date object (1 ~ 31)

Date.gethours ()//23 returns the hour of the date object (0 ~ 23)

Date.getminutes ()//30 returns the minute of the Date object (0 ~ 59)

Date.getseconds ()//54 returns the number of seconds of the date object (0 ~ 59)

Date.getmilliseconds () returns the milliseconds of the Date object (0 ~ 999)

Date.gettime () returns the number of milliseconds since January 1, 1970

Four: each case conversion

1. var time = "2017-12-12" converted to millisecond timestamp

New Date (Time.replace (/-/g, "/")). GetTime ()//1513008000000

2. var time = 1513008000000 converted to "2017-12-12"

Note: Time cannot be a string if number

var date = new Date (time)

var year1 = Date2.getfullyear ()
var month = Date2.getmonth ()
var today = Date2.getdate ()
var Time1 = year1 + "-" + month + "-" + Today

The use of Date objects in JS