JavaScript: Splitting and joining dates in mm/dd/yyyy format -

i'm having bit of difficulty comparing 2 dates entered in mm/dd/yyyy format. have following code written try convert them yyyy-mm-dd format, , display error div if start date greater end date:

for(i=0; i<=9; i++) {    datefrom+i = document.getelementbyid('projdatefrom'+i).value;    dateto+i = document.getelementbyid('projdateto+i').value;    datefrom+i = datefrom+i.split("/").reverse().join("-");    dateto+i = dateto+i.split("/").reverse().join("-");    if(datefrom+i > dateto+i)    {        document.getelementbyid('dateerror').style.display = '';        return false;    } 

when enter dates on form in mm/dd/yyyy format, , deliberately enter projdatefrom greater projdateto, nothing happens. missing?

moment.js fantastic date tool: http://momentjs.com/docs/#/displaying/difference/

here's fiddle take date format, convert proper javascript object wrapped many convenient date methods.

example fiddle: http://jsfiddle.net/cfa2e/3

var diff = end.diff(start, 'days'); 

where end date compare against start