JSFiddle - React, Tailwind, and code Playground

JavaScript

var todayDate = "10-05-2012"; // A sample date
var compareDate1 = "10-05-2012";
var compareDate2 = "03-05-2012";
var compareDate3 = "10-07-2012";

compareDates(todayDate, compareDate1);
compareDates(todayDate, compareDate2);
compareDates(todayDate, compareDate3);

function compareDates(date1String, date2String) {
    var date1 = parseDate(date1String);
    var date2 = parseDate(date2String);
    if(date1.getTime() > date2.getTime()) {
      alert("First date(" + date1String + ") is older than second date(" + date2String + ").");                
    } else if(date1.getTime() < date2.getTime()) {
      alert("First date(" + date1String + ") is younger than second date(" + date2String + ").");                
    } else {
      alert("The dates are the same day");   
    }
}

function parseDate(stringDateParam) {
    var parsedDay = parseInt(stringDateParam.substring(0,2));
    var parsedMonth = parseInt(stringDateParam.substring(3,5))-1;
    var parsedYear = parseInt(stringDateParam.substring(6,10));
    var parsedDate = new Date(parsedYear, parsedMonth, parsedDay, 0 , 0, 0, 0);
    return parsedDate;
}