How do you parse a date from an HTML5 date input?

Question

I have an input on my webpage that I am able to set the date on by getting an ISO string and pulling out the first 10 characters.

date = new Date();
dateInpu         


        

Answer 1

as said by Marty the problem is the difference between the representation of the timezone of the input (UTC defined by W3C) and the JS timezone (local). The solution is to getTimezoneOffset (which is in minutes) and convert everything to milliseconds:

var today = document.getElementById("myInputDate").valueAsDate;
var tomorrow = new Date(today.valueOf() + 86400000 + (today.getTimezoneOffset() * 60000));

86400000 = milliseconds of a day

today.getTimezoneOffset() * 60000 = timezoneOffset in milliseconds