JSFiddle - React, Tailwind, and code Playground

HTML

<input type="text" id="data" value="12/12/2014">

JavaScript

function isAValidDate () {
    
    console.log(dateValue);
   var dateParts = dateValue.split ("/");
   if (dateParts.length != 3) return false;
    
   var day, month, year;
   month = dateParts[0]-1;
   day = dateParts[1];
   year = dateParts[2];
 
   var parsedDate = new Date (dateValue);
    
   if (month != parsedDate.getMonth()) return false;
 
   if (day != parsedDate.getDate()) return false;
 
   if (year != parsedDate.getFullYear()) return false;
 
   return true;
}
console.log(document.getElementById('dateValue').value);