Question
Can someone suggest a way to compare the values of two dates greater than, less than, and not in the past using JavaScript? The values will be coming from text boxes.
Answer
The [Date object](https://developer.mozilla.org/en-
US/docs/Web/JavaScript/Reference/Global_Objects/Date) will do what you want -
construct one for each date, then compare them using the >, <, <= or
>=.
The ==, !=, ===, and !== operators require you to use date.getTime()
as in
var d1 = new Date();
var d2 = new Date(d1);
var same = d1.getTime() === d2.getTime();
var notSame = d1.getTime() !== d2.getTime();
to be clear just checking for equality directly with the date objects won't work
var d1 = new Date();
var d2 = new Date(d1);
console.log(d1 == d2); // prints false (wrong!)
console.log(d1 === d2); // prints false (wrong!)
console.log(d1 != d2); // prints true (wrong!)
console.log(d1 !== d2); // prints true (wrong!)
console.log(d1.getTime() === d2.getTime()); // prints true (correct)
I suggest you use drop-downs or some similar constrained form of date entry rather than text boxes, though, lest you find yourself in input validation hell.
For the curious, [date.getTime()
documentation](https://developer.mozilla.org/en-
US/docs/Web/JavaScript/Reference/Global_Objects/Date/getTime):
Returns the numeric value of the specified date as the number of milliseconds since January 1, 1970, 00:00:00 UTC. (Negative values are returned for prior times.)
