How to set start day time to particular time in momentjs

Question

I'm trying to set the start time of the day to a particular time. currently, in momentjs, I can get startOf day like this

 let now = moment()
 console.log('now', now.toString()) 
 console.log('start Day', now.startOf('day').toString()) // Thu Oct 07 2021 00:00:00 GMT+0530
 console.log('end day', now.endOf('day').toString()) //Thu Oct 07 2021 23:59:59 GMT+0530

is there any way so I can set my day start from particular time like I want to start my day from

Thu Oct 07 2021 08:00:00 GMT+0530

and end on

Thu Oct 07 2021 07:59:59 GMT+0530

Answer 1

You should probably write your own function in order to achieve this.

function customStartOf(momentObj) {
  return momentObj.clone().startOf('day').hours(8);
}

function customEndOf(momentObj) {
  // I assume that end of the day is bigger than start of the day
  return momentObj.clone().endOf('day').add(1, 'days').hours(7);
}

let now = moment();

console.log('now', now.toString()) ;
console.log('start Day', now.startOf('day').toString());
console.log('end day', now.endOf('day').toString());

console.log('custom start Day', customStartOf(now).toString());
console.log('custom end day', customEndOf(now).toString());

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>

Answer 2

You have to take into account the timezone.

let myDate = new Date();

const timezoneOffset = moment(myDate).utcOffset();

moment(myDate).utc().add(timezoneOffset, 'minutes').startOf('day').format();
moment(myDate).utc().add(timezoneOffset, 'minutes').endOf('day').format();