未捕获的TypeError：对象.NumCon没有方法'apply'

Question

I want run a jquery code that if number value text input was under of 7 , the result is false. but i get following error:

 Uncaught TypeError: Object .NumCon has no method 'apply'
     f.event.dispatch
     f.event.add.h.handle.i

What do i do?

Demo: http://jsfiddle.net/FZMsP/

This is my code:

<form>
    <input type="password" name="user_pass" class="NumCon" id="7">
</form>

​
function NumCon() {
    var result = true;
    $(this).closest("form").find('.NumCon').each(function () {
        var size = this.value.length;
        var NumVal = $(this).attr('id');
        if (size <= NumVal) {
            $(this).css("background", "#ffc4c4");
            result = false;
        }else{
            $(this).css("background-color", "#ffffec");
        }
    });
}

$('.NumCon').live('keyup', NumCon());​

Answer 1

You're calling your function from inside of the definition line, which is (for some reason) then interpreted as an object.

$('.NumCon').on('keyup', NumCon);​

Solves your problem.

Answer 2

.live has now been depreciated, seems youre now meant to use: $(document).on("click", "a.offsite", function(){ alert("Goodbye!"); });

Jquery .live

Answer 3

​The solution is

$('.NumCon').on('keyup', yourFunction(yourParameters));

source http://api.jquery.com/on/