Clash Royale CLAN TAG

Calculate days in month with getDate Javacript

I'm using the following JS to calculate X days ahead of today's date. The output seems to work fine, except the result doesn't consider the days in each month. Therefore, if today is the 26th and I add 9 days, it's outputting the day as the 35th which obviously doesn't make sense.

<script>
window.onload=function(){
var dateObj = new Date();

var months = ['January','February','March','April','May','June','July','August','September','October','November','December'];

var month = months[dateObj.getMonth()]; //months from 1-12
var day = dateObj.getUTCDate() +9;
var year = dateObj.getUTCFullYear();

newdate = day + " " + month + " " + year;
document.getElementById("date").innerHTML=(newdate);
}
</script>


How can we get it to output the accurate date?

setUTCDate()

2 Answers
2

You should be able to do this using the Date.setDate function, instead of getting the day and then adding 9 to it

window.onload = function() {
var dateObj = new Date();
// -------------- add this line -------//
dateObj.setDate(dateObj.getDate() + 9);

var months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];

var month = months[dateObj.getMonth()]; //months from 1-12
var day = dateObj.getUTCDate(); //+9; remove +9
var year = dateObj.getUTCFullYear();

newdate = day + " " + month + " " + year;
document.getElementById("date").innerHTML = (newdate);

}


You should update your date using setDate() using getDate() to get the current date of the month and adding 9.

setDate()

getDate()

window.onload = function() {
var dateObj = new Date();
// add 9 days here
dateObj.setDate(dateObj.getDate() + 9);

var months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', 'September', 'October', 'November', 'December'];

var month = months[dateObj.getMonth()]; //months from 1-12
var day = dateObj.getUTCDate();
var year = dateObj.getUTCFullYear();

newdate = day + " " + month + " " + year;
document.getElementById("date").innerHTML = (newdate);

}

<span id="date"></span>

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