undefined value when getting value from json variable

Question

I have a c# webservice that returns json data. Here is the data that is being returned.

[ { "destination": "pandora.com", "hits": 9 }, 
{ "destination": "google.com", "hits": 2 }, 
{ "destination": "msftncsi.com", "hits": 2 }, 
{ "destination": "nmlsconsumeraccess.org", "hits": 1 }, 
{ "destination": "facebook.com", "hits": 1 }, 
{ "destination": "gravatar.com", "hits": 1 }, 
{ "destination": "iheart.com", "hits": 1 }, 
{ "destination": "kiss1041fm.com", "hits": 1 }, 
{ "destination": "live.com", "hits": 1 }, 
{ "destination": "microsoft.com", "hits": 1 }, 
{ "destination": "today.com", "hits": 1 }, 
{ "destination": "update.microsoft.com", "hits": 1 }, 
{ "destination": "xsitesnetwork.com", "hits": 1 }, 
{ "destination": "youtube-nocookie.com", "hits": 1 }, 
{ "destination": "youtube.com", "hits": 1 }, 
{ "destination": "zillow.com", "hits": 1 } ]

Here is my javascript:

ret = Convert2Json.Convert(OnComplete, OnTimeOut, OnError); //this is my webservice

function OnComplete(arg) {

    $('#label').text(arg); //when I set this label to arg
    //I get the json data correctly as above

    var list = {
        "entries": arg
    };

    alert(list.entries[0].destination);
    //this gives me undefined when it popups
}

function OnTimeOut(arg) {
    alert("TimeOut encountered when calling server");
}

function OnError(arg) {
    alert("Error encountered when calling server");
}

If I define list myself as follows, it works:

var list = { "entries": [{ "destination": "pandora.com", "hits": 9 }, { "destination": "google.com", "hits": 2 }, { "destination": "youtube.com", "hits": 2 }, { "destination": "facebook.com", "hits": 1 }, { "destination": "fdic.gov", "hits": 1 }, { "destination": "GOV_new", "hits": 1 }, { "destination": "iheart.com", "hits": 1 }, { "destination": "jcpportraits.com", "hits": 1 }, { "destination": "kiss1041fm.com", "hits": 1 }, { "destination": "live.com", "hits": 1 }, { "destination": "msftncsi.com", "hits": 1 }, { "destination": "publix.com", "hits": 1 }, { "destination": "today.com", "hits": 1 }, { "destination": "xsitesnetwork.com", "hits": 1 }, { "destination": "youtube-nocookie.com", "hits": 1 }] };

Here is what Convert2Json.Convert does

[WebMethod]
[ScriptMethod(ResponseFormat = ResponseFormat.Json)]
public string Convert() {




    using (SqlConnection conn = new SqlConnection("Server=localhost;Initial Catalog=Testing_Server;Trusted_Connection=True;"))
    {

        SqlCommand cmd = new SqlCommand("SELECT Destination as destination, count(distinct(source)) as hits FROM [Carlos_Test] where GETDATE() < DATEADD(MINUTE,5,time) and destination not in ('google-analytics.com','gstatic.com','googleadservices.com','download.windowsupdate.com') group by Destination order by hits DESC", conn);




        conn.Open();


        List<VisitedSites> slist = new List<VisitedSites>();

        SqlDataReader reader = cmd.ExecuteReader();

        while (reader.Read()) {



            VisitedSites vs = new VisitedSites();
            vs.destination = reader["destination"].ToString();
            vs.hits = Int32.Parse(reader["hits"].ToString());

            slist.Add(vs);

        }





        string jSon = JsonConvert.SerializeObject(slist, Formatting.Indented);


        return jSon;
    }



}

public class VisitedSites {

    public string destination;
    public int hits;


}

console.log(list, arg); --- for debugging purposes use console.log, not alert — zerkms
– zerkms, Commented Feb 12, 2013 at 21:14
possible duplicate of I have a nested data structure / JSON, how can I access a specific value? — Felix Kling
– Felix Kling, Commented Feb 12, 2013 at 21:16
You might have to parse the JSON (arg) first. If $('#label').text(arg); shows you the data as you posted it, then arg is a string, not an array. — Felix Kling
– Felix Kling, Commented Feb 12, 2013 at 21:17
@Felix Kling: then the Convert2Json.Convert call looks odd. Though your comment makes much sense — zerkms
– zerkms, Commented Feb 12, 2013 at 21:19
@zerkms: Well, I don't know what Convert2Json.Convert does. I have seen many odd things ;) One time I stumbled upon a library that had a method called toJSON, which returned a JavaScript object. — Felix Kling
– Felix Kling, Commented Feb 12, 2013 at 21:19

zerkms · Accepted Answer · 2013-02-12 21:15:41Z

4

According to what you shown - the arg is an array.

So, say alert(list.entries[0].destination); could work, giving you the first element, but the alert(list.entries.destination); won't because list.entries is an array, that doesn't have .destination property specified.

answered Feb 12, 2013 at 21:15

zerkms

256k73 gold badges447 silver badges551 bronze badges

Sign up to request clarification or add additional context in comments.

3 Comments

user541597 Over a year ago

edited code. list.entries[0].destination is what I am using. That is what is giving me undefined.

zerkms Over a year ago

@user541597: without console.log results (see my first comment to the question) it's not possible to say anything else for sure

Felix Kling Over a year ago

@user541597: Did you parse the JSON like I suggested?

Collectives™ on Stack Overflow

undefined value when getting value from json variable

1 Answer 1

3 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

3 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related