how to do Date Comparision in javascript? - javascript-events

Question

I need to create the javascript Function based on Date Comparison.which means,To compare the Currentday with Currentday+7.
function a(value)
{
//here how to get current date
//here how to add 7 days with current date
return addedvalue;
}
function b(value)
{
var s=a(value);
//again getting current date here
//check this function current date with s.then if its true means show,
alert('next 7th day is'+s);
}
How to do this?

Answer 1

var now = new Date();// gives you the current date.
var sevenDaysFromNow = new Date();
sevenDaysFromNow.setDate(now.getDate() + 7); // adds seven days.
function compareDates(d, dd) {
return d - dd;
};
Date comparison
If you have two date objects, in this case now and sevenDaysFromNow, subtracting them now - sevenDaysFromNow will return the difference in milliseconds between the two dates. You can convert the difference to a different time unit using simple maths.
var ms = sevenDaysFromNow - now;
var hoursDiff = ms / 1000 / 60 / 60;
var daysDif = ms / 1000 / 60 / 60 / 24;
Working fiddle

Answer 2

This will give you the current date:
new Date()
This will transform it into milliseconds since EPOCH:
(new Date()).valueOf()
This will calculate how much time 7 days are:
7 * 24 * 60 * 60 * 1000
This will transform your integer back to a date:
new Date(any number of millisecond since EPOCH);
To complete the example:
function a() {
return new Date((new Date()).valueOf() + (7 * 60 * 60 * 24 * 1000));
}

Answer 3

Date comparison is done using the DateDiff function.
We dont have any comparison function for Date