jQuery Validation plugin: how to check if an element is valid?

Question

A little bit of context:

I'm using the jQuery Validation plugin to validate a sign-up form. I now want to implement an ajax call to check whether the user name is available in the system, and I want to make this ajax call only if the userName value is a valid one as per the rules set in $(form).validate();

I want something like:

$("#userName").keyup(function () {
    if ($("#userName").isValid()) {
        //make ajax called
    }
});

I searched the documentation but i couldn't identify the solution to my problem.

Answer 1

$("#userName").keyup(function () {
    if ($("#userName").valid() == true ) {
        //make ajax called
    }
});

http://docs.jquery.com/Plugins/Validation/valid

Note: To those who do not click the link. You have to call $("#myform").validate(); first.

Answer 2

Validator.element()

Description: Validates a single element, returns true if it is valid, false otherwise.

http://jqueryvalidation.org/Validator.element