jquery username validation

[eluser]Unknown[/eluser]
I want to check username required field, length and this username is exist on database or not.

I found many example

user_name:
{
required:true,
minlength:5,
remote:base_url()+controllername+functionname

}


it is not working at all.


On this otherhand, if i use :

$(document).ready(function(){

$('#user_name').keyup(function(){

if( $('#user_name').val().length >= 5 )
{
var username = $('#user_name').val();
getResult(username);
}
else{


}
return false;
})
function getResult(name){
var baseurl = $('.hiddenUrl').val();
$('.checkUser').addClass('preloader');
$.ajax({
url : baseurl + 'administrator/checkuser/getResultfromdb/' + name,
cache : false,
success : function(response){
$('.checkUser').removeClass('preloader');
if(response == 'userOk') $('.checkUser').removeClass('userNo').addClass('userOk');
else $('.checkUser').removeClass('userOk').addClass('userNo');;
}
})
}
})



========================
<?php if ( ! defined('BASEPATH')) exit('No direct script access allowed');

class Checkuser extends CI_Controller {

function __construct()
{
parent::__construct();
}

function index()
{

$this->load->view('administrator/checkuserView');
}
function getResultfromdb($username){

$this->db->where('username',$username);
$query = $this->db->get('users')->num_rows();
if($query == 0 ) echo 'userOk';
else echo 'userNo';
}

function checkusername()
{
//$username = $_REQUEST["email"];
$username =$this->input->post('user_name') ;
// $_REQUEST["user_name"];
if ($username == "[email protected]"){
echo "false";
} else {
echo "true";
}
}



}

?>

=========================

It works fine to checking username already exist.

But required field and minlength field is not working.


How to check username already field by using remote: rule?

[eluser]anis2505[/eluser]

View Part

Code:

$(’#user_name’).keyup(function(){
var url = '<?php echo site_url('checkuser/checkusername');?>'+'/'+$(this).val();
$.getJSON(url, function(data) {
                     if(data['error']=='none'){
                           alert('Valid usernma');
                     }else{
                          alert(data['error'];
                     }

  });


});

Controller Part

Code:

function checkusername($username){
  $data = array()
                if(already exists){
                     $data['error']='The username already exist';
  }else{
                     $data['error'='none';
                }
                echo json_encode($data);
}

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