Jbom - pastebin.com/uEEvZEpK

gistfile1.js

//JAVASCRIPT
$(document).ready(function(){
    CLICKIT_core.init();
    CLICKIT_contract_form.init();
});

var CLICKIT_config = {
    URLs : {
        checkName : 'index.php/users/getnames'
    }
}

var CLICKIT_ajax = {
    checkName : function (name,callback){
        $.ajax({
            url: CLICKIT_config.URLs.checkName,
            type: "POST",
            async: true,
            data: "name="+name,
            dataType:"json",
            success: function (data){
                callback(data);
            }
        });
    }
}

var CLICKIT_contract_form={
    init:function(){
        //Submit Event
        $('#contract form#check_name').bind('submit',function(){
            CLICKIT_contract_form.onSubmit();
            return false;
        });
    },
    onSubmit:function(){
        var name = $('#contract form#check_name input[id="url"]').val();
        if($.trim(name) != ""){
            $('#contract form#check_name button span').addClass('loading');
            $('#contract form#check_name button span').html('cargando');
            CLICKIT_ajax.checkName(name,CLICKIT_contract_form.onReceive);
        }
    },
    onReceive:function(data){
        //myJson = eval("(" + data + ");");
        $('#contract form#check_name button span').html('FIN');
        //console.log(data.name);
        console.log(data.result);
    }
    
}

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//PHP
        public function getnames(){
            $jsondata['name'] = $_POST['name'];
            $jsondata['result'] = 'ok';
            header('Content-type: application/json');
            echo json_encode($jsondata);
        }