CODEWITHSUNDEEP
c#json
brnwdrng
brnwdrng

Reputation: 521

JSON Deserialization: How to get values out of a JSON array of objects

I've successfully deserialized this JSON string in C#, but can't extract the values from the objects nested in the array:

JavaScriptSerializer js = new JavaScriptSerializer();

string json = 
  {"key":"1234","status":"ok","members":
      [{"id":7,"name":"Joe"},
   {"id":2,"name":"Robert"},
   {"id":18,"name":"Tim"}
      ]
   }

var d = js.Deserialize < dynamic > (json);

string _key = d["key"]; // this works

Array _members = d["members"]; // this works, length = 3

But I'm having trouble extracting the values out of the objects by name, e.g, this isn't right, but essentially I want

_members[0]["name"] or, _members[0].name

I think the deserializer makes the objects inside the array dictionaries, but I think I'm clearing missing something...

Upvotes: 5

Views: 52893

Answers (3)

koko
koko

Reputation: 335

It's a bit late for an answer but I've been trying to figure this out and thought I should post somewhere what worked for me.

I wanted to use foreach so:

foreach (var member in json["members"])
    {
        Console.WriteLine(member["name"]);
    }

and by the way, (for some reason like in my project) if you have nested arrays, e.g.

string json = 
{"key":"1234","status":"ok",
 "members":[
   {"items"[
       {"id":7,"name":"Joe"},
       {"id":2,"name":"Robert"},
       {"id":18,"name":"Tim"}
   ]}
]}

Then:

foreach (var member in json["members"])
    {
        foreach (var item in member["items"])
        {  
            Console.WriteLine(item["name"]);
        }
    }

Upvotes: 4

meklarian
meklarian

Reputation: 6625

You were quite close in syntax. The key here is that d["members"] is of type Object[] / object[]. Instead of Array, you can use dynamic[] and everything works just fine.

Also note that even this declaration isn't explicitly necessary, as shown in DPeden's updated sample.

Here is the code for your updated snippet (I used a console app to test):

JavaScriptSerializer js = new JavaScriptSerializer();
dynamic d = js.Deserialize<dynamic>(json);

string key = d["key"];
string status = d["status"];
dynamic[] members = d["members"];

Console.WriteLine("key = {0}", key);
Console.WriteLine("status = {0}", status);

Console.WriteLine("members.length = {0}", members.Length);
Console.WriteLine("members type name = {0}", members.GetType().Name);
Console.WriteLine("d[\"members\"] type name = {0}", d["members"].GetType().Name);

And here is additional code showing array and member access.

Console.WriteLine("--");

for (int i = 0; i < members.Length; i++)
{
    Console.WriteLine("members[{0}][\"id\"] = {1}", i, members[i]["id"]);
    Console.WriteLine("members[{0}][\"name\"] = {1}", i, members[i]["name"]);
}

Console.WriteLine("--");

Console.WriteLine("{0}", d["members"][0]["id"]);
Console.WriteLine("{0}", d["members"][0]["name"]);

Console.ReadKey();

Upvotes: 2

David Peden
David Peden

Reputation: 18454

I recommend using Json.NET to do what you're doing. The following code does what you want:

    JObject jObject = JObject.Parse(json);
    JToken memberName = jObject["members"].First["name"];
    Console.WriteLine(memberName); // Joe

Via LINQ to Json.

Update:

    var js = new JavaScriptSerializer();
    var d = js.Deserialize<dynamic>(json);
    Console.WriteLine(d["members"][0]["name"]); // Joe

Also works fine.

Upvotes: 18

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