Check times span over two days as well as within the same day using momentjs

Given the following two times without dates and using moment, how can I best check the following two scenarios based on 24 hours times:

1)

let startTime = "22:00:00";
let endTime = "02:00:00";

Using the startTime I need to set some flag (boolean) indicating that the endTime has spanned over to the next day and not within the same 24 hour period of the startTime?

2)

let startTime = "22:00:00";
let endTime = "23:53:00";

the same as item (1) but this time setting a flag indicating that the startTime and endTime are within the same 24 hour period

Answer

Here’s a snippet. Took the liberty to replace let by const, as there are no expected modifications to the variables.

const startTime_1 = "22:00:00";
const endTime_1 = "02:00:00";

const momentStart_1 = moment(startTime_1, 'hh:mm:ss');
const momentEnd_1 = moment(endTime_1, 'hh:mm:ss');

const hasSpanned_1 = momentStart_1.isAfter(momentEnd_1);
console.log(`${startTime_1} -> ${endTime_1} ==> Spanned: ${hasSpanned_1}`); // true.

const startTime_2 = "22:00:00";
const endTime_2 = "23:53:00";

const momentStart_2 = moment(startTime_2, 'hh:mm:ss');
const momentEnd_2 = moment(endTime_2, 'hh:mm:ss');

const hasSpanned_2 = momentStart_2.isAfter(momentEnd_2);
console.log(`${startTime_2} -> ${endTime_2} ==> Spanned: ${hasSpanned_2}`); // true.

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