How Can I Accurately Compare Dates in JavaScript?

Comparing Dates with JavaScript

To compare the values of two dates in JavaScript, utilizing the standard operators such as greater than, less than, and not equal, one can utilize the Date object. By constructing a Date object for each of the dates, these comparisons can be performed effectively.

Utilizing the ==, !=, ===, and !== operators in comparison of dates requires the use of date.getTime(). This method returns the numeric value of the specified date as the number of milliseconds since January 1, 1970.

Examine the following code snippet:

var d1 = new Date();
var d2 = new Date(d1);
var same = d1.getTime() === d2.getTime();
var notSame = d1.getTime() !== d2.getTime();

This demonstration illustrates that direct comparison of date objects will not suffice. Instead, comparing the result of date.getTime() is necessary for accurate equality checks.

For input validation purposes, employing drop-downs or other constrained forms of date entry is recommended as opposed to relying solely on text boxes. This will help prevent input validation issues.

It's noteworthy that date.getTime() offers detailed information regarding the specified date, representing the number of milliseconds since January 1, 1970, 00:00:00 UTC.

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