I have a 24 hour time looks like 14:00 and I want to convert this into today's utc time string format which is looks like Mon Dec 19 2022 14:00:00 GMT 0530 (India Standard Time). How can I do this in javascript.

CodePudding user response：

That isn't UTC, that's local time in India.

The output looks like the now-defined¹ output of the Date toString method, so you need to:

1. Create a Date instance for today with 14:00 as the time (local time).
2. Use toString

// Your time string
const time = "14:00";
// Split it into hours and minutes as numbers
const [hours, minutes] = time.split(":").map(Number);
// Get a date for "now"
const dt = new Date();
// Set its hours, minutes, seconds, and milliseconds
dt.setHours(hours, minutes, 0, 0);
// Get the string
const str = dt.toString();

console.log(str);

For me here in England that outputs Mon Dec 19 2022 14:00:00 GMT 0000 (Greenwich Mean Time), but for someone in India it should output something in that time zone.

¹ For a very long time, the output of toString wasn't precisely defined. As of recent specifications, it is.

CodePudding user response：

You can use the Date object and the toUTCString method.

const timeString = "2022-12-19T14:30:00";
const date = new Date(timeString);
const utcTimeString = date.toUTCString();
console.log(utcTimeString); // "Tue, 20 Dec 2022 00:30:00 GMT"