I am using momentjs to try to get the difference in days between 2 dates but the days returned are not correct. The start date is 2021-04-05 and the end date is 2021-04-09 and it is returned 4 instead of 5.
I did a console log and this is what I get.
here is my code:
const [startDate, setStartDate] = useState(new Date())
const [endDate, setEndDate] = useState(new Date())
const ed = moment(endDate)
const sd = moment(startDate)
console.log(ed)
console.log(sd)
<h6>Total Number of Days: {ed.diff(sd, 'days')}</h6>
Where did I get it wrongly? Many thanks in advance and greatly appreciate any helps. Thanks
Here is how I got the difference and hope it will be useful to anyone. thanks
{Math.floor(( Date.parse(endDate) - Date.parse(startDate) ) / 86400000)}
Related
moment("20-52", "YY-ww").add(1, "week").format("YY-ww");
The result is 20-01 but I'd expect it to be 21-01
Any ideas? Is this a bug or am I doing it wrong?
You must use ISO week of years (WW), with lowercase ww moment get the week of the last day of the week in question.
const ue = moment("20-52", "YY-WW", true).add(1, "week").format("YY-WW");
console.log(ue);
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>
I need to find if currentDate time (unix) and lastFetchedTime(unix) is greater than 30 minutes in moment.js.
How can compare the subtracted value from 30 minutes in moment?
lastFetchedTime(unix) is equivalent to the previous Date.now()..
const now = moment(Date.now());
const lastFetched = 1598578706;
const checkTime = now.diff(lastFetched, 'minutes') > 30 ;
You can use momentJS duration function to get the difference between two times which are in unix format.
Firstly, you need to convert the unix format to human readable time and then get the difference of current time and lastFetched time using asMinutes function of duration
If the difference is greater then 30 then do something else or do something else.
Live Demo:
const now = moment().unix()
const lastFetched = 1598597404;
const duration = moment.duration(moment.unix(now).diff(moment.unix(lastFetched)));
const getMinutes = duration.asMinutes();
if (getMinutes > 30) {
console.log('Minutes are GREATER then 30 minutes - from now')
} else {
console.log('Minutes are LESS then 30 minutes - from now')
}
<script src="//cdnjs.cloudflare.com/ajax/libs/moment.js/2.8.4/moment.js"></script>
In my angular web application, I want to compare two dates to see if a person is less than 18 years old when she/he entered the company. Here is the code I use to do this:
const dayOfBirth = moment(formControl.value, this.dateFormat, true).startOf('day');
const entranceDateControl = this.wizardFormGroup.get('entranceDate');
const entranceDate = moment(entranceDateControl.value, this.dateFormat, true).startOf('day');
// Check validation rule R3: Age is less than 18 compared to entrance date
const difference = moment.duration(Math.abs(entranceDate.diff(dayOfBirth)));
if (difference.years() < 18) {
const validationMessage = this.getValidationMessage('R3', formControlName);
return validationMessage ? validationMessage.message : null;
}
As you can see, I am using startOf('day') to get rid of any time component so that I only handle dates. I use diff() to get the difference between two dates and then duration() to convert the difference to years, months, days, etc. Using this code, the validation message should NOT show when the person is turning 18 years old on the day when she/he entered the company.
Upon testing this, I came across what is, in my opinion, strange behavior. Depending on months and years used, it gave different results. For instance, for these dates it was Ok:
dayOfBirth = 1998-03-01, 1998-04-01, ..., 2000-02-01
entranceDate = 2016-03-01, 2016-04-01, ..., 2018-02-01
But the following dates returned the validation message:
dayOfBirth = 2000-03-01, 2000-04-01, ..., 2002-02-01
entranceDate = 2018-03-01, 2000-04-01, ..., 2020-02-01
After these dates, i.e. using 2002-03-01 and onward, it works again. I also got wrong result for the dates preceding 1998-03-01.
Now, I had a closer look at the Duration object and I noticed that for the times where it was less than 18 years, it had calculated 864 milliseconds less then when it came to the right conclusion that it was 18 years between the dates.
Correct duration
----------------
dayOfBirth = 1998-03-01, 1998-04-01, ..., 2000-02-01
entranceDate = 2016-03-01, 2016-04-01, ..., 2018-02-01
Duration = 568080000000 ms
Wrong duration
--------------
dayOfBirth = 2000-03-01, 2000-04-01, ..., 2002-02-01
entranceDate = 2018-03-01, 2000-04-01, ..., 2020-02-01
Duration = 567993600000 ms
Duration difference
-------------------
568080000000 - 567993600000 = 86400000 ms = 24 hours = 1 day
Has anyone an explanation for this? Can it be considered a bug in momentjs? Any viable workaround for this?
I didn't go into details in moment source code but it seems duration() is playing tricks with you. Simplify the code and rely only on diffas follow and you should be good (at least it seems to work for the samples you provided). And it's easier on the eyes :)
const moment = require('moment')
const dayOfBirth = moment('2000-03-01').startOf('day');
const entranceDate = moment('2018-03-01').startOf('day');
const difference = entranceDate.diff(dayOfBirth, 'years')
if (difference < 18) {
console.log( '<18')
} else {
console.log( '>=18')
}
will output >=18
I'm using Moment.js and for some (probably basic) reason I'm not getting the result I'm expecting:
let date = moment("1995-01-25");
date.add(2, 'm');
console.log(date.month()); // Expected 2, outputs 0
You have to use uppercase M for adding months, lowercase m stands for minutes, see add docs:
Key | Shorthand
-------------------
months | M
minutes | m
Here a working sample:
let date = moment("1995-01-25");
date.add(2, 'm');
console.log(date.month());
console.log(date.format()); //1995-01-25T00:02:00
let date2 = moment("1995-01-25");
date2.add(2, 'M');
console.log(date2.month()); // 2
console.log(date2.format()); // 1995-03-25T00:00:00
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.min.js"></script>
I am trying to return the month number passing the month name using MomentJS. For example if I pass "July" to moment() I would expect 7 to be returned.
After reading through the docs I tried several different ways, and this way came close...
console.log(moment().month("July"));
In the console, buried in the response I could see this...
_monthsParse: Array[7]
Could anyone please tell me how to return the month number using MomentJS correctly?
Try :
moment().month("July").format("M");
Relevant documentation: http://momentjs.com/docs/#/get-set/month/
alert(moment().month("July").format("M"));
<script src="https://momentjs.com/downloads/moment.min.js"></script>
Anybody looking to get month name from month number then you can try :
const number = 1; // 0 = Jan & 11 = Dec
moment().month(number).format("MMM"); // Feb
Use following to get full month name :
const number = 1; // 0 = January & 11 = December
moment().month(number).format("MMMM"); // February
To use simple month number try this:
const month = 2 //Feb
moment(month, 'M').format('MMMM');
##get month name in moment js with node js
moment() give today date
format("DD-MMMM-YYYY") / output 18-May-2020
format("DD-MM-YYYY") / output 18-05-2020
- sperator you can use /
```
var moment = require('moment');
m_date = moment().format("DD-MMMM-YYYY");
console.log("moment date :", m_date)
```
##output
```
moment date : 18-May-2020
```
Read Officail Docdescription here