Custom date format with jQuery validation plugin

You can create your own custom validation method using the addMethod function. Say you wanted to validate "dd/mm/yyyy":

$.validator.addMethod(
    "australianDate",
    function(value, element) {
        // put your own logic here, this is just a (crappy) example
        return value.match(/^\d\d?\/\d\d?\/\d\d\d\d$/);
    },
    "Please enter a date in the format dd/mm/yyyy."
);

And then on your form add:

$('#myForm')
    .validate({
        rules : {
            myDate : {
                australianDate : true
            }
        }
    })
;

nickf's answer is good, but note that the validation plug-in already includes validators for several other date formats, in the additional-methods.js file. Before you write your own, make sure that someone hasn't already done it.

I personally use the very good http://www.datejs.com/ library.

Docco here: http://code.google.com/p/datejs/wiki/APIDocumentation

You can use the following to get your Australian format and will validate the leap day 29/02/2012 and not 29/02/2011:

jQuery.validator.addMethod("australianDate", function(value, element) { 
    return Date.parseExact(value, "d/M/yyyy");
});

$("#myForm").validate({
   rules : {
      birth_date : { australianDate : true }
   }
});

I also use the masked input plugin to standardise the data http://digitalbush.com/projects/masked-input-plugin/

$("#birth_date").mask("99/99/9999");

Jon, you have some syntax errors, see below, this worked for me.

  <script type="text/javascript">
$(document).ready(function () {

  $.validator.addMethod(
      "australianDate",
      function (value, element) {
        // put your own logic here, this is just a (crappy) example 
        return value.match(/^\d\d?\/\d\d?\/\d\d\d\d$/);
      },
      "Please enter a date in the format dd/mm/yyyy"
    );

  $('#testForm').validate({
    rules: {
      "myDate": {
        australianDate: true
      }
    }
  });

});