Get Length of array JSON.Net

Question

How can I get the length of a JSON Array I get using json.net in C#? After sending a SOAP call I get a JSON string as answer, I use json.net to parse it.

Example of the json I got:

{"JSONObject": [
    {"Id":"ThisIsMyId","Value":"ThisIsMyValue"},
    {"Id":"ThisIsMyId2","Value":"ThisIsMyValue2"}
]}

And I parse it and write it in console:

var test = JObject.Parse (json);
Console.WriteLine ("Id: {0} Value: {1}", (string)test["JSONObject"][0]["Id"], (string)test["JSONObject"][0]["Value"]);

This works like a spell, only I don't know the length of the JSONObject, but I need to do it in a for loop. I only have no idea how I can get the length of test["JSONObject"]

But something like test["JSONObject"].Length would be too easy I guess :(..

musefan · Accepted Answer · 2013-09-26T10:15:38.340

83

You can cast the object to a JArray and then use the Count property, like so:

JArray items = (JArray)test["JSONObject"];
int length = items.Count;

You can then loop the items as follows:

for (int i = 0; i < items.Count; i++)
{
    var item = (JObject)items[i];
    //do something with item
}

According to Onno (OP), you can also use the following:

int length = test["JSONObject"].Count();

However, I have not personally confirmed that this will work

edited Sep 26 '13 at 10:15

answered Sep 26 '13 at 10:07

musefan

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Don't you need to cast to `JArray` for that? – svick Sep 26 '13 at 10:12
I tried that, as I seen that somewhere else. But somewhy I did not try Count() instead, what seems to work. I'm very sorry for my stupidity :O – Onno Sep 26 '13 at 10:12
@Onno: Are you saying that `Count()` works? If so I can update the answer – musefan Sep 26 '13 at 10:13
Yes, I just tried it and it works. Count gives me an error in the compiler – Onno Sep 26 '13 at 10:14
Use ".Count", not ".Count()" – Andrew Jay Jun 13 '17 at 15:59
If the json string includes both objects (with curly brackets {}) and arrays (with square brackets [])...I found using JObject worked with both types. JArray only worked with arrays. – rr789 Aug 27 '18 at 17:52

score 3 · Answer 2 · answered Nov 06 '20 at 15:03

3

The easiest and cleanest way I found:

int length = test["JSONObject"].Count;

answered Nov 06 '20 at 15:03

George Chalhoub

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This returns the number of `JTokens` which in some cases might NOT be the expected size of the array – konkri Aug 02 '22 at 13:21

score 2 · Answer 3 · answered Mar 15 '18 at 10:10

2

You can use below line to get the length of JSON Array in .Net (JArray) .

 int length = ((JArray)test["jsonObject"]).Count;

answered Mar 15 '18 at 10:10

ZaidRehman

1,631
2
19
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score 2 · Answer 4 · edited Jun 27 '19 at 07:20

2

Just try this:

var test= ((Newtonsoft.Json.Linq.JArray)json).Count;

edited Jun 27 '19 at 07:20

jkdev

11,360
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answered Jun 27 '19 at 06:59

arul pushpam

501
6
6

score 1 · Answer 5 · answered May 29 '20 at 22:17

This worked for me supposing the json data is in a json file. In this case, .Length works but no intellisence is available:

    public ActionResult Index()
    {
        string jsonFilePath = "C:\\folder\\jsonLength.json";
        var configFile = System.IO.File.ReadAllText(jsonFilePath);

        JavaScriptSerializer jss = new JavaScriptSerializer();
        var d = jss.Deserialize<dynamic>(configFile);

        var jsonObject = d["JSONObject"];
        int jsonObjectLength = jsonObject.Length;
        return View(jsonObjectLength);
    }

Get Length of array JSON.Net

5 Answers5

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