Question

I have combined itechroom checkUserName function
with JohnP’s run js after user finished typing function
but it doesn’t seem to work…

$(document).ready(function(){
    //JohnyP keydowntimer
    var timer = null;
    $('#username').keydown(function(){
        clearTimeout(timer);
        timer = setTimeout(checkUserName(usercheck), 1000);
    });

    //http://www.itechroom.com
    function checkUserName(usercheck){
            $('#usercheck').html('<img src="images/ajax-loader.gif" />');
            $.post("checkuser.php", {username: usercheck} , function(data){
                if (data != '' || data != undefined || data != null){
                    $('#usercheck').html(data);
                }
            });
    }
})

I’ve tried onblur="checkUserName(this.value)" and it worked well…

Answer 1

It doesn’t appear that you’re declaring usercheck anywhere (or, at least, aren’t setting its value within the snippet). What seems to be missing is…

$('#username').keydown(function () {
    var usercheck = $(this).val(); // ...this line.
    // etc.
});

But, you also have an issue with setTimeout. As it stands, checkUserName(usercheck) is being called immediately and the return value is then being passed to setTimeout.

Since you need to pass an argument, you can wrap the call to checkUserName in a new function which will be called when the timeout expires and will in turn call checkUserName:

setTimeout(function () {
    checkUserName(usercheck);
}, 1000);