从ajax调用中检索json_encoded PHP对象值？

Question

My ajax:

$.ajax(
        {
            type:'POST',
            url: 'ajax.php',                  //the script to call to get data
            data: {request: 'getUser',id:id},
            dataType: 'json',                //data format
            complete: function(data)          //on receive of reply
            {
                console.log(data); 
            }
        });

My php file that handles the ajax request(ajax.php):

elseif ($_POST['request'] == 'getUser')
    {
        $DAO = new UserDAO;
        $q = $DAO->ajaxGetUser($_POST['id']);
        echo json_encode($q);
    }

ajaxGetUser function:

public function ajaxGetUser($id)
    {
        $q = $this->db->prepare('SELECT * FROM user WHERE userId=:id');
        $q->bindValue(':id', $id, PDO::PARAM_INT);
        $q->execute();
        $r = $q->fetch(PDO::FETCH_OBJ);
        unset($r->userPassword);
        return $r;
    }

console.log(data) is showing me the object in the "ResponseJSON" on firebug, but when I try something like console.log(data.userName) , console.log(data[0].userName) , they're undefined, since i'm not very good in ajax i've been looking many threads but couldn't find one that could help me.

I guess the json is already parsed since dataType is set to "json", how can I access the User object with all its properties? Thanks for your help

readyState 4

responseJSON
    Object { userId="6", userName="321", more...}

responseText
    "{"userId":"6","userName...":null,"userStatus":"0"}"

status 200  
statusText "OK" 
abort function()    
always function()   
complete function()
done function()
error function()
fail function()
getAllResponseHeaders function()    
getResponseHeader function()
overrideMimeType function()
pipe function()
progress function()
promise function()
setRequestHeader function()
state function()
statusCode function()
success function()  
then function()

Answer 1

Set a success handler instead of complete :

The callback hooks provided by $.ajax() are as follows:

[...]
4. success callback option is invoked, if the request succeeds. It receives the returned data, a string containing the success code, and the jqXHR object.
[...]
6. complete callback option fires, when the request finishes, whether in failure or success. It receives the jqXHR object, as well as a string containing the success or error code.

The code would look like:

success: function(data)
{
    console.log(data, data.userId, data.userName); 
}

Answer 2

It seems data was an object, I managed to get the user object was by using data.responseJSON , so data.responseJSON.userName for the name.

I don't know why it would return in this way through.