How to use JSON.NET to serialize an array of objects

Question

I remember that one of my friends told me that I can throw anything into JSON.NET and serialize them into JSON format.

    public string GetRecords(string apiKey, DateTime start, DateTime end)
    {
        var user = db.Users.SingleOrDefault(u => u.Id == apiKey);

        if (user == null)
        {
            return string.Empty;
        }

        var records = db.Histories.Where(h => h.Date >= start && h.Date <= end);

        JavaScriptSerializer s = new JavaScriptSerializer();

        return JsonConvert.SerializeObject(records);
    }

But now I got an exception:

There is already an open DataReader associated with this Command which must be closed first.

What can I do to resolve this?

score 3 · Accepted Answer · answered Jun 01 '14 at 07:40

3

Call .ToList() on records, before passing it to JsonConvert.SerializeObject

answered Jun 01 '14 at 07:40

3dd

2,520
13
20

score 0 · Answer 2 · edited May 23 '17 at 10:28

0

You probably didn't enable multiple active result sets (MARS) in your config file.

Follow this link

Basically need to add

"MultipleActiveResultSets=True"

Or you could eager load as suggested by 3dd

More help here There is already an open DataReader associated with this Command which must be closed first

edited May 23 '17 at 10:28

Community

1
1

answered Jun 01 '14 at 07:41

Navyseal

891
1
13
36

How to use JSON.NET to serialize an array of objects

2 Answers2