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javascript - How to get the minimum and maximum date

How do I get the smallest and biggest date. I see that the smallest number can be got like this:

Number.MIN_VALUE

Date does not have this. Is there a way to find the smallest and biggest date

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Date does not have this

Actually, it does, but only indirectly. According to the specification, a Date object's milliseconds-since-the-Epoch value can only be in the range -8640000000000000 to 8640000000000000.

So the minimum date is new Date(-8640000000000000) (Tue, 20 Apr -271821 00:00:00 GMT), and the maximum date is new Date(8640000000000000) (Sat, 13 Sep 275760 00:00:00 GMT).

If you wanted, you could put those on the Date function as properties:

Date.MIN_VALUE = new Date(-8640000000000000);
Date.MAX_VALUE = new Date(8640000000000000);

...but since Date instances are mutable, I probably wouldn't, because it's too easy to accidentally modify one of them. An alternative would be to do this:

Object.defineProperties(Date, {
    MIN_VALUE: {
      value: -8640000000000000 // A number, not a date
    },
    MAX_VALUE: {
      value: 8640000000000000
    }
});

That defines properties on Date that cannot be changed that have the min/max numeric value for dates. (On a JavaScript engine that has ES5 support.)


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