Example of a custom validation method for the jQuery Validation plugin to ensure one date is greater than the other

customValidatorExample.js

jQuery.validator.addMethod("dateComparison",function(value,element) {
    var result= true;			
    if($("#startDateOptionLater:checked").length== 1) 
      {
        var dateArray= $("#startDate").val().split("/");
        var startDateObj= new Date(dateArray[2],(dateArray[0]-1),dateArray[1],0,0,0,0);
      } 
    else 
      {
        var exactDate= new Date();
        var year= exactDate.getFullYear();
        var month= exactDate.getMonth();
        var day= exactDate.getDate();
        var startDateObj= new Date(year,month,day,0,0,0,0);
      }
				
    var endDateArray= $("#endDate").val().split("/");
    var endDateObj= new Date(endDateArray[2],(endDateArray[0]-1),endDateArray[1],0,0,0,0);
    var startDateMilliseconds= startDateObj.getTime();
    var endDateMilliseconds= endDateObj.getTime();
				
    if (endDateMilliseconds <= startDateMilliseconds) 
      {
        result= false;
      }
     
    return result;

 },"The ending date must be a later date than the start date");