moment check if date is older than date code example

Example 1: moment js check if date is greater than

let A = moment('2020-01-02');
let B = moment('2020-01-01');
let C = moment('2020-01-03');
console.log(A.diff(B, 'days'));// => 1
console.log(A.diff(C, 'days'));// => -1

Example 2: moment js - to find if dates are same by day

var iscurrentDate = startTime.isSame(new Date(), "day");
if(iscurrentDate) {

}