JSON object undefined

Question

I've got a an AJAX page request that uses a php file designed to handle queries to my MySQL database. The php file works just fine, but for some reason it's not being nice with me. Here's what I have:

    function updateForm(){
        ID = $('#listings').val();
        $.ajax({
            type: "POST",
            url: 'query.php',
            data: "query=true" +
                    "&id=" + ID,
            datatype: 'json',
            success: function(data) {
                alert(data);
                updatePreview();
            }
        });
    }

gives me a popup with:

{"results":[{"ID":"12","area":"Hoboken","bedrooms":"5","fullbath":"3","halfbath":"1","remarks":"No remarks to speak of.","sqft":"2500","photos":null,"price":"1000","fee":null,"realtor":"Jane Doe","phone":"555-555-5555","address":"10th & Willow","bix":"1"}]}

but as soon as I change it to:

    function updateForm(){
        ID = $('#listings').val();
        $.ajax({
            type: "POST",
            url: 'query.php',
            data: "query=true" +
                    "&id=" + ID,
            datatype: 'json',
            success: function(data) {
                alert(data.results);
                updatePreview();
            }
        });
    }

the popup just says undefined.

Ultimately, I want to parse out information and update my page accordingly, but I can't seem to access any of the properties of this JSON object. What's going on?

EDIT:

Here's the code from the php file:

if (isset($_POST['query'])){
    if (isset($_POST['id'])){
        $query = 'SELECT * FROM bix WHERE ID=' . get_post('id');
        $listing = mysql_query($query);
        print_json($listing);
    }
}
function print_json($var){
    $output = array();
    while($row = mysql_fetch_assoc($var)) {
        $output["results"][] = $row;
    }
    echo json_encode($output);
}

function get_post($var)
{
    return mysql_real_escape_string($_POST[$var]);
}

can you post your server side code?

Tim Wickstrom
– Tim Wickstrom

2012-03-27 21:18:36 +00:00
Commented Mar 27, 2012 at 21:18 — Tim Wickstrom
– Tim Wickstrom, Commented Mar 27, 2012 at 21:18
also if you console.log() both what do you get?

Tim Wickstrom
– Tim Wickstrom

2012-03-27 21:18:54 +00:00
Commented Mar 27, 2012 at 21:18 — Tim Wickstrom
– Tim Wickstrom, Commented Mar 27, 2012 at 21:18
maybe you didn't capitalize the T in dataType...

Timmerz
– Timmerz

2012-03-27 21:37:39 +00:00
Commented Mar 27, 2012 at 21:37 — Timmerz
– Timmerz, Commented Mar 27, 2012 at 21:37

Eugene Retunsky · Accepted Answer · 2012-03-27 21:31:17Z

2

If it shows you a string in the alert popup it means that the data is a string, not JSON. For JSON it shows [Object object].

Check the response type. It should be applicaton/json or applicaton/javascript, not text/plain or something like that.

UPDATE: also make sure the server doesn't return the whole string in quotes. E.g. "[..]" - it just a string then. So use FireBug or Chrome Developer Tools to see what is the actual response. It might help to understand why jQuery doesn't handle it properly.

edited Mar 27, 2012 at 21:31

answered Mar 27, 2012 at 21:15

Eugene Retunsky

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1 Comment

Tim Wickstrom Over a year ago

This is interesting however according to the jQuery docs a datatype: 'json', is supposed to do the lifting for you... can you post your server side code?

Timmerz · Accepted Answer · 2012-03-27 21:55:26Z

1

did you try capitalizing the T in dataType, on the ajax call already?

answered Mar 27, 2012 at 21:55

Timmerz

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Comments

SSH This · Accepted Answer · 2012-03-27 21:12:26Z

1

You should console.log(data) instead, with this you can see the keys that you can use to access the data.

answered Mar 27, 2012 at 21:12

SSH This

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Comments

Timmerz · Accepted Answer · 2012-03-27 21:18:04Z

1

I don't think it's coming back as parsed json..it's coming back as a string I believe...

use:

var x = jQuery.parseJSON(data);
alert(x.results)

answered Mar 27, 2012 at 21:18

Timmerz

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5 Comments

mavix Over a year ago

It should, though. The documentation says that datatype: 'json' returns a JSON object, not a string.

Timmerz Over a year ago

did you try capitalizing the T in dataType, on the ajax call already?

mavix Over a year ago

Ahhh, that's totally what the problem was.

mavix Over a year ago

If you write that in as a response I'll give you the check mark!

Timmerz Over a year ago

I added a new response. you can check that. glad that fixed it.

chadpeppers · Accepted Answer · 2012-03-27 21:12:58Z

0

Try using data instead of data.results or targeting the data.id or data.area and see what it comes up with

answered Mar 27, 2012 at 21:12

chadpeppers

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Comments

Ray · Accepted Answer · 2012-03-27 21:19:17Z

0

As Eugene pointed out, data is a string. Try eval:

var stuff = eval(data);
alert(stuff.results);

EDIT: this works, but jQuery.parseJSON is probably cooler.

answered Mar 27, 2012 at 21:19

Ray

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