How to add days to Date?

You can create one with:-

Date.prototype.addDays = function(days) {
    var date = new Date(this.valueOf());
    date.setDate(date.getDate() + days);
    return date;

var date = new Date();


This takes care of automatically incrementing the month if necessary. For example:

8/31 + 1 day will become 9/1.

The problem with using setDate directly is that it’s a mutator and that sort of thing is best avoided. ECMA saw fit to treat Date as a mutable class rather than an immutable structure.

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