I have start and end properties in range object. And each property has time value.
range = {
start: Tue Jul 07 2020 10:58:05,
end: Wed Jul 08 2020 10:58:05
}
then I have to make an array of length 30 that contains random time between range.start and range.end.
[Tue Jul 07 2020 11:00:05, Tue Jul 07 2020 13:49:12, Tue Jul 07 2020 15:22:54... Wed Jul 08 2020 12:51:05, Wed Jul 08 2020 15:24:13]
I think I can do it using new Array(30).fill(dates) but have no clue what to put it inside dates.
This converts your dates to timestamps, then generates random numbers in-between and converts those back to dates. Note: added timezone
var start = new Date('Tue Jul 07 2020 10:58:05 GMT-0400').getTime();
var end = new Date('Wed Jul 08 2020 10:58:05 GMT-0400').getTime();
var dates = Array(30).fill().map(() => {
return new Date(
Math.floor(Math.random() * (end - start)) + start
).toString();
});
Results in:
["Wed Jul 08 2020 01:55:53 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 16:58:52 GMT-0400 (Eastern Daylight Time)"
"Wed Jul 08 2020 00:02:45 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 15:33:55 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 20:16:20 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 15:25:33 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 17:15:14 GMT-0400 (Eastern Daylight Time)"
"Wed Jul 08 2020 02:20:32 GMT-0400 (Eastern Daylight Time)"
"Tue Jul 07 2020 23:25:54 GMT-0400 (Eastern Daylight Time)"
...]
Edit: for unique dates you can do something like this:
var start = new Date('Tue Jul 07 2020 10:58:05 GMT-0400').getTime();
var end = new Date('Wed Jul 08 2020 10:58:05 GMT-0400').getTime();
var dates = [];
while(dates.length < 30) {
let date = new Date(
Math.floor(Math.random() * (end - start)) + start
).toString();
if (!dates.includes(date)) {
dates.push(date);
}
}
I wouldn't use this if the start and end dates are very close (within seconds of eachother) and/or the output array is very large. It will block thread.
I'm not big fan of Array(n).fill() just to create an empty array with n undefined elements as the basis for a loop when the array is then discarded.
A for loop is likely less code and more efficient, e.g. (same algorithm as GitGitBoom):
let range = {
start: new Date(2020,6,7,10,58,05),
end: new Date(2020,6,8,10,58,05)
}
let result = [];
for (let s = +range.start, diff = range.end - s, i = 30; i; --i) {
result.push(new Date(s + Math.random() * diff).toString());
}
console.log(result.sort());
If you're prepared to use var, the result array can be declared in the for loop initialiser too.
Assuming you have a randomTimeGenerator, function:
var randomTimes = [];
var i=30; while(i--){randomTimes.push(randomTimeGenerator(i, randomTimes))}
i am getting the format from server is : Mon Sep 05 2016 00:00:00 GMT+0530 (India Standard Time)
Some times I am getting 05/09/2016.(dd/MM/yyyy)
How can check whether i am getting Mon Sep 05 2016 00:00:00 GMT+0530 (India Standard Time) this format?
Thanks in advance!
I assume irrespective of the format, you want to create date object and use it. For such situations, you should use moment.js. But if not, you can try something like this:
function getDateFromString(str) {
var date1 = null;
if (str.trim().indexOf(" ") > -1)
date1 = new Date(str);
else {
var seperator = null;
if (str.indexOf("/") > -1)
seperator = "/"
else
seperator = "-"
str = str.split(seperator).reverse().join(seperator);
console.log(str)
date1 = new Date(str);
}
return date1;
}
var a = "Mon Sep 05 2016 00:00:00 GMT+0530 (India Standard Time)";
var b = "05/09/2016";
alert(getDateFromString(a));
alert(getDateFromString(b));
I am trying to calculate number of weeks in a month using moment js. But I am getting wrong results for some months like May 2015 and August 2015.
I am using this code.
var start = moment().startOf('month').format('DD');
var end = moment().endOf('month').format('DD');
var weeks = (end-start+1)/7;
weeks = Math.ceil(weeks);
Is there any prebuilt method in moment JS for getting number of weeks.
I have created this gist that finds all the weeks in a given month and year. By calculated the length of calendar, you will know the number of weeks.
https://gist.github.com/guillaumepiot/095b5e02b4ca22680a50
# year and month are variables
year = 2015
month = 7 # August (0 indexed)
startDate = moment([year, month])
# Get the first and last day of the month
firstDay = moment(startDate).startOf('month')
endDay = moment(startDate).endOf('month')
# Create a range for the month we can iterate through
monthRange = moment.range(firstDay, endDay)
# Get all the weeks during the current month
weeks = []
monthRange.by('days', (moment)->
if moment.week() not in weeks
weeks.push(moment.week())
)
# Create a range for each week
calendar = []
for week in weeks
# Create a range for that week between 1st and 7th day
firstWeekDay = moment().week(week).day(1)
lastWeekDay = moment().week(week).day(7)
weekRange = moment.range(firstWeekDay, lastWeekDay)
# Add to the calendar
calendar.push(weekRange)
console.log calendar
Can be easily done using raw javascript:
function getNumWeeksForMonth(year,month){
date = new Date(year,month-1,1);
day = date.getDay();
numDaysInMonth = new Date(year, month, 0).getDate();
return Math.ceil((numDaysInMonth + day) / 7);
}
You get the day index of the first day, add it to the number of days to compensate for the number of days lost in the first week, divide by 7 and use ceil to add 1 for the simplest overflow in the next week
It display the list of weeks in a month with 'moment.js'.
It has been written in typescript with angular 6+.
Install moment with 'npm i moment'
Inside the ts file.
weeks_in_month() {
let year = 2019; // change year
let month = 4; // change month here
let startDate = moment([year, month - 1])
let endDate = moment(startDate).endOf('month');
var dates = [];
var weeks = [];
var per_week = [];
var difference = endDate.diff(startDate, 'days');
per_week.push(startDate.toDate())
let index = 0;
let last_week = false;
while (startDate.add(1, 'days').diff(endDate) < 0) {
if (startDate.day() != 0) {
per_week.push(startDate.toDate())
}
else {
if ((startDate.clone().add(7, 'days').month() == (month - 1))) {
weeks.push(per_week)
per_week = []
per_week.push(startDate.toDate())
}
else if (Math.abs(index - difference) > 0) {
if (!last_week) {
weeks.push(per_week);
per_week = [];
}
last_week = true;
per_week.push(startDate.toDate());
}
}
index += 1;
if ((last_week == true && Math.abs(index - difference) == 0) ||
(Math.abs(index - difference) == 0 && per_week.length == 1)) {
weeks.push(per_week)
}
dates.push(startDate.clone().toDate());
}
console.log(weeks);
}
Result:
Array of date moments.
[Array(6), Array(7), Array(7), Array(7), Array(3)]
0: (6) [Mon Apr 01 2019 00:00:00 GMT+0530 (India Standard Time),
Tue Apr 02 2019 00:00:00 GMT+0530 (India Standard Time),
Wed Apr 03 2019 00:00:00 GMT+0530 (India Standard Time),
Thu Apr 04 2019 00:00:00 GMT+0530 (India Standard Time),
Fri Apr 05 2019 00:00:00 GMT+0530 (India Standard Time),
Sat Apr 06 2019 00:00:00 GMT+0530 (India Standard Time)]
1: (7) [Sun Apr 07 2019 00:00:00 GMT+0530 (India Standard Time),
Mon Apr 08 2019 00:00:00 GMT+0530 (India Standard Time),
Tue Apr 09 2019 00:00:00 GMT+0530 (India Standard Time),
Wed Apr 10 2019 00:00:00 GMT+0530 (India Standard Time),
Thu Apr 11 2019 00:00:00 GMT+0530 (India Standard Time),
Fri Apr 12 2019 00:00:00 GMT+0530 (India Standard Time),
Sat Apr 13 2019 00:00:00 GMT+0530 (India Standard Time)]
2: (7) [Sun Apr 14 2019 00:00:00 GMT+0530 (India Standard Time),
Mon Apr 15 2019 00:00:00 GMT+0530 (India Standard Time),
Tue Apr 16 2019 00:00:00 GMT+0530 (India Standard Time),
Wed Apr 17 2019 00:00:00 GMT+0530 (India Standard Time),
Thu Apr 18 2019 00:00:00 GMT+0530 (India Standard Time),
Fri Apr 19 2019 00:00:00 GMT+0530 (India Standard Time),
Sat Apr 20 2019 00:00:00 GMT+0530 (India Standard Time)]
3: (7) [Sun Apr 21 2019 00:00:00 GMT+0530 (India Standard Time),
Mon Apr 22 2019 00:00:00 GMT+0530 (India Standard Time),
Tue Apr 23 2019 00:00:00 GMT+0530 (India Standard Time),
Wed Apr 24 2019 00:00:00 GMT+0530 (India Standard Time),
Thu Apr 25 2019 00:00:00 GMT+0530 (India Standard Time),
Fri Apr 26 2019 00:00:00 GMT+0530 (India Standard Time),
Sat Apr 27 2019 00:00:00 GMT+0530 (India Standard Time)]
4: (3) [Sun Apr 28 2019 00:00:00 GMT+0530 (India Standard Time),
Mon Apr 29 2019 00:00:00 GMT+0530 (India Standard Time),
Tue Apr 30 2019 00:00:00 GMT+0530 (India Standard Time)]
EDIT:
NEW and hopefully very correct implementation:
function calcWeeksInMonth(date: Moment) {
const dateFirst = moment(date).date(1);
const dateLast = moment(date).date(date.daysInMonth());
const startWeek = dateFirst.isoWeek();
const endWeek = dateLast.isoWeek();
if (endWeek < startWeek) {
// Yearly overlaps, month is either DEC or JAN
if (dateFirst.month() === 0) {
// January
return endWeek + 1;
} else {
// December
if (dateLast.isoWeekday() === 7) {
// Sunday is last day of year
return endWeek - startWeek + 1;
} else {
// Sunday is NOT last day of year
return dateFirst.isoWeeksInYear() - startWeek + 1;
}
}
} else {
return endWeek - startWeek + 1;
}
}
Outputs the following values for the following dates:
calcWeeksInMonth(moment("2016-12-01")); // 5
calcWeeksInMonth(moment("2017-01-01")); // 6
calcWeeksInMonth(moment("2017-02-01")); // 5
calcWeeksInMonth(moment("2017-03-01")); // 5
calcWeeksInMonth(moment("2017-04-01")); // 5
calcWeeksInMonth(moment("2017-05-01")); // 5
calcWeeksInMonth(moment("2017-06-01")); // 5
calcWeeksInMonth(moment("2017-07-01")); // 6
calcWeeksInMonth(moment("2017-08-01")); // 5
calcWeeksInMonth(moment("2017-09-01")); // 5
calcWeeksInMonth(moment("2017-10-01")); // 6
calcWeeksInMonth(moment("2017-11-01")); // 5
calcWeeksInMonth(moment("2017-12-01")); // 5
calcWeeksInMonth(moment("2018-01-01")); // 5
OLD and very incorrect implementation:
calcWeeksInMonth(date) {
const dateFirst = moment(date).date(1)
const dateLast = moment(date).date(date.daysInMonth())
const startWeek = dateFirst.week()
const endWeek = dateLast.week()
if (endWeek < startWeek) {
return dateFirst.weeksInYear() - startWeek + 1 + endWeek
} else {
return endWeek - startWeek + 1
}
}
This seems to output correct results, feedback welcome if there is something I missed!
function getWeekNums(momentObj) {
var clonedMoment = moment(momentObj), first, last;
// get week number for first day of month
first = clonedMoment.startOf('month').week();
// get week number for last day of month
last = clonedMoment.endOf('month').week();
// In case last week is in next year
if( first > last) {
last = first + last;
}
return last - first + 1;
}
javaScript version here
var year = 2021
var month = 6
var startDate = moment([year, month])
//Get the first and last day of the month
var firstDay = moment(startDate).startOf('month')
var endDay = moment(startDate).endOf('month')
//Create a range for the month we can iterate through
var monthRange = moment.range(firstDay, endDay)
//Get all the weeks during the current month
var weeks = []
var indexOf = [].indexOf;
monthRange.by('days', function (moment) {
var ref;
if (ref = moment.week(), indexOf.call(weeks, ref) < 0) {
return weeks.push(moment.week());
}
});
var calendar, firstWeekDay, i, lastWeekDay, len, week, weekRange;
calendar = [];
for (i = 0, len = weeks.length; i < len; i++) {
week = weeks[i];
// Create a range for that week between 1st and 7th day
firstWeekDay = moment().week(week).day(0);
lastWeekDay = moment().week(week).day(6);
weekRange = moment.range(firstWeekDay, lastWeekDay);
// Add to the calendar
calendar.push(weekRange);
}
This is the best way out , works well
moment.relativeTime.dd = function (number) {
// round to the closest number of weeks
var weeks = Math.round(number / 7);
if (number < 7) {
// if less than a week, use days
return number + " days";
} else {
// pluralize weeks
return weeks + " week" + (weeks === 1 ? "" : "s");
}
}
Source:How to get duration in weeks with Moment.js?
I have not seen a solution that works in all circumstances. I tried all of these but they all are flawed in one way or another. Ditto with several moment.js github threads. This was my crack at it:
getNumberOfWeeksInMonth = (momentDate) => {
const monthStartWeekNumber = momentDate.startOf('month').week();
const distinctWeeks = {
[monthStartWeekNumber]: true
};
let startOfMonth = momentDate.clone().startOf('month');
let endOfMonth = momentDate.clone().endOf('month');
// this is an 'inclusive' range -> iterates through all days of a month
for (let day = startOfMonth.clone(); !day.isAfter(endOfMonth); day.add(1, 'days')) {
distinctWeeks[day.week()] = true
}
return Object.keys(distinctWeeks).length;
}
function weeksInMonth(date = null){
let firstDay = moment(date).startOf('month');
let endDay = moment(date).endOf('month');
let weeks = [];
for (let i = firstDay.week(); i <= endDay.week(); i++){
weeks.push(i)
}
return weeks;
}
Here is a simple way of doing it (based on a solution posted above):
const calcWeeksInMonth = (momentDate) => {
const dateFirst = moment(momentDate).date(1)
const dateLast = moment(momentDate).date(momentDate.daysInMonth())
const startWeek = dateFirst.isoWeek()
const endWeek = dateLast.isoWeek()
if (endWeek < startWeek) {
// cater to end of year (dec/jan)
return dateFirst.weeksInYear() - startWeek + 1 + endWeek
} else {
return endWeek - startWeek + 1
}
}
As far as I can tell, it works correctly for any date thrown at it, but feedback is always welcome!
Throwing this into the mix
import moment from "moment";
export const calcWeeksInMonth = date => {
let weekMonthEnds = moment(date)
.date(moment(date).daysInMonth())
.week();
let weekMonthStarts = moment(date)
.date(1)
.week();
return weekMonthEnds < weekMonthStarts
? moment(date).isoWeeksInYear() - weekMonthStarts + 1
: weekMonthEnds - weekMonthStarts + 1;
};
var month = moment().month();
var startOfMonth = month.startOf("month");
var endOfMonth = month.endOf("month");
var startWeekNumber = startOfMonth.isoWeek();
var endWeekNumber = endOfMonth.isoWeek();
var numberOfWeeks = (endWeekNumber - startWeekNumber + 1);
console.log(numberOfWeeks);
If you have selectedDate value that is give you opportunity to detect which month is active now:
private calculateNumberOfWeeks(): number {
const end = moment(this.selectedDate).endOf('month');
const startDay = moment(this.selectedDate)
.startOf('month')
.day();
const endDay = end.day();
const endDate = end.date();
return (startDay - 1 + endDate + (endDay === 0 ? 0 : 7 - endDay)) / 7;
}
/UPDATE/
Solution below did not take in consideration jump to the new year.
Here is the improved solution.
const getNumberOfWeeksInAMonth = (currentMoment: moment.Moment) => {
const currentMomentCopy = cloneDeep(currentMoment)
const startOfMonth = currentMomentCopy.startOf('month')
const startOfISOWeek = startOfMonth.startOf('isoWeek')
let numberOfWeeks = 0;
do {
numberOfWeeks++
MomentManager.addWeek(startOfISOWeek)
} while (currentMoment.month() === startOfISOWeek.month())
return numberOfWeeks;
}
I have found another solution with momentjs.
const getNumberOfWeeksInMonth = (moment: moment.Moment) => {
const startWeek = moment.startOf('month').isoWeek()
const endWeek = moment.endOf('month').isoWeek()
return endWeek - startWeek + 1
}
I am trying UTCString to above format. I can able to convert, problem is after conversion it shows a day before.
var newDate = this.getCellDate(target);
console.log(newDate); --> Dec 05 2014 00:00:00 GMT+0800 (Malay Peninsula Standard Time)
cstDate = newDate.toISOString();
console.log(cstDate); -- > 2014-12-04 --- > **Expected --> 2014-12-05**
Use Date.UTC() method
var now = new Date(), // my date Thu Dec 04 2014 13:02:15 GMT+0300 (RTZ 2 (зима))
year = now.getFullYear(),
month = now.getMonth(),
day = now.getDay(),
hours = now.getHours(),
minutes = now.getMinutes(),
utcDate;
utcDate = new Date(Date.UTC(year, month, day, hours, minutes)); // Thu Dec 04 2014 16:02:00 GMT+0300 (RTZ 2 (зима))
Ext.Msg.alert('UTC Date', Ext.Date.format(utcDate, 'Y-m-d'));
Look at this "Thu Dec 04 2014 16:02:00" - i got utc time(+3 hours)
Fiddle example
Yeah i got the solution. I should not toISOString. instead i need to use toLocaleDateString
custdate = newDate.toLocaleDateString();
dueDate= custdate.split("/").reverse().join("-");
I have two variables namely
date1 = Mon Nov 25 2013 00:00:00 GMT+0530 (IST)
date2 = Mon Nov 25 2013 14:13:55 GMT+0530 (IST)
When I compare the two dates I get that date2 is greater which I need is correct. But I do not want to check the time part of the two dates I have. How could I get the date part alone from these two dates and compare it?
var today = new Date(); //Mon Nov 25 2013 14:13:55 GMT+0530 (IST)
d = new Date(my_value); //Mon Nov 25 2013 00:00:00 GMT+0530 (IST)
if(d>=today){ //I need to check the date parts alone.
alert(d is greater than or equal to current date);
}
Try clearing the time using Date.setHours:
dateObj.setHours(hoursValue[, minutesValue[, secondsValue[, msValue]]])
Example Code:
var today = new Date();
today.setHours(0, 0, 0, 0);
d = new Date(my_value);
d.setHours(0, 0, 0, 0);
if(d >= today){
alert(d is greater than or equal to current date);
}
The best way would be to modify the accepted answer's if statement as follows
if(d.setHours(0,0,0,0) >= today.setHours(0,0,0,0))
In this way, you can easily check for equality as well because the return type for setHours() is integer.
Try:
var today = new Date(); //Mon Nov 25 2013 14:13:55 GMT+0530 (IST)
var d = new Date(my_value); //Mon Nov 25 2013 00:00:00 GMT+0530 (IST)
var todayDateOnly = new Date(today.getFullYear(),today.getMonth(),today.getDate()); //This will write a Date with time set to 00:00:00 so you kind of have date only
var dDateOnly = new Date(d.getFullYear(),d.getMonth(),d.getDate());
if(dDateOnly>=todayDateOnly){
alert(d is greater than or equal to current date);
}
var StartDate = $("#StartDate").val();
var EndDate = $("#EndDate").val();
if ((( EndDate - StartDate)/ (86400000*7))<0)
{
alert("Start Date Must Be Earlier Than End Date"); $("#StartDate").focus();
error = true;
return false;
}