JavaScript Formatting string date yyyymmdd to MM-DD-YYYY

[runfast]

I am trying to format a string date yyyymmdd into a date field 'mm-dd-yyyy' to update a date filed on a table. Here is the code i am trying to use

var g = new GlideRecord('table1);
    g.query();
    var newDate = g.getValue('end_date'); //end_date string comes as //yyyyMMDD (20200219)
    var year1 = newDate.substr(0,4);
    var month1 = newDate.substr(4,2);
    var date1 = newDate.substr(6,2);
    var newDate = month1 + "-" + date1 + "-" + year1;
    gs.log(newDate);//The date is showing as expected ('02-19-2020')
    gs.log(date2);
    g.setValue('expiration_date',newDate);
    g.update();

This is inserting wrong date something like this "04-12-0011". So I am trying to figure out on how to format this date. Any directions or guidance is greatly appreciated.

 

[Krygore]

I'm not wholeheartedly familiar with setting date formats in JS, but this link from W3Schools.com should help give you some insight to setting the format you are after! https://www.w3schools.com/js/js_date_formats.asp

Cheers,