validation - Using jQuery validate rule twice for a field -

i'm trying validate input field holds user's date of birth, , need two checks - 1. make sure user 18 years old , 2. make sure his/her age isn't on 100.

my custom validate method -

$.validator.addmethod(        "datediff",        function(value, element, diff_years) {           var curr_date = new date().getfullyear();           var element_date = date.parse($(element).val()).getfullyear();           return element_date >= curr_date - diff_years;        } ); 

and here's how add rule.

var validator = $('form').validate({      rules: {         'dob': {datediff: 18}      },      messages: {          dob: {datediff: 'you have 18 or more!'}      } }); 

how reuse datediff rule twice, can both checks? tried appending datediff rule, didn't work.

edit: need show 2 distinct messages - example - 1. "you have 18 or more" first condition, , "you cannot more 100" second.

if need 2 unique messages, you'll need 2 unique rules/methods. can put common code single function , call within custom method.

something this...

function datediff(value, diff_years) {     var curr_date = new date().getfullyear();     var element_date = date.parse(value.getfullyear();     return element_date >= curr_date - diff_years; }  $.validator.addmethod( "over18", function(value, element) {     // custom function below     // var result = datediff(value, 18);     // return true if age greater 18     // return false , error message display }, "you must on 18");  $.validator.addmethod( "under100", function(value, element) {     // custom function below     // var result = datediff(value, 100);     // return true if age less 100     // return false , error message display }, "you must under 100");  $('form').validate({      rules: {          dob: {              over18: true,              under100: true          }      } });