Unity C# convert String to Json array Erro

Question

I have two class:

[System.Serializable]
public class oneTask{
    public string id;
    public string username;
    public string task;
    public string category;
    public string time;
    public bool status;

}
public class taskcollection{
    public oneTask[] tasksjson;
}

And my conversion is

taskcollection temptasks = JsonUtility.FromJson<taskcollection> (jsonString);

But it will come with an Error: ArgumentException: JSON must represent an object type. UnityEngine.JsonUtility.FromJson[taskcollection] (System.String json)

Could anyone help with how to convert string to JSON array in Unity? The JSON is like:

[{"id":"1","username":"Hanslen","task":"Writing PEC cw2","category":"Study","time":"2016-11-18 00:00:00","status":false},{"id":"2","username":"Hanslen","task":"Prepare for MLE presentation","category":"Study","time":"2016-11-24 00:00:00","status":false},{"id":"3","username":"Hanslen","task":"Some testing task1","category":"Life","time":"2017-02-20 22:09:52","status":false},{"id":"4","username":"Hanslen","task":"Some testing task2","category":"Movie","time":"2017-02-20 22:09:52","status":true},{"id":"5","username":"Hanslen","task":"Some testing task3","category":"Life","time":"2017-02-20 22:09:55","status":false},{"id":"6","username":"Hanslen","task":"Some testing task4","category":"Shopping","time":"2017-02-20 22:09:55","status":false},{"id":"7","username":"Hanslen","task":"server","category":"test","time":"2017-02-21 17:38:32","status":true},{"id":"8","username":"Hanslen","task":"Website task adding","category":"Study","time":"2017-02-21 17:40:58","status":false},{"id":"9","username":"Hanslen","task":"Another website task adding","category":"undefined","time":"2017-02-21 17:53:01","status":false},{"id":"10","username":"Hanslen","task":"adasdasdsa","category":"Life","time":"2017-02-21 17:53:18","status":false}]

EDIT:

The Json from server does not contain anything about taskcollection class. It only has info about the oneTask class. You have to do JsonHelper.FromJson<oneTask>(jsonString); not JsonHelper.FromJson<taskcollection>(jsonString);

You have to fix the Json then use JsonHelper to deserialize it.

string fixJson(string value)
{
    value = "{\"Items\":" + value + "}";
    return value;
}

//Fix Json
jsonString = fixJson(jsonString);
//Deserialize it
oneTask[] temptasks = JsonHelper.FromJson<oneTask>(jsonString);

@MMK I put that on the top of task collection class but that does not work.. — user6142261, Feb 26 '17 at 12:26
do you have these using statments in your code.... using UnityEngine; using System; using System.Collections; using System.Collections.Generic; — MMK, Feb 26 '17 at 12:26
This is a json array. By the way, did you create the json you posted by hand? How did you get that json? — Programmer, Feb 26 '17 at 12:35
@Programmer I get it from the webpage.. I try you link,, but still failed....I am still working with that.. — user6142261, Feb 26 '17 at 12:41
Check the Edit I made into your question. Make sure to also include `[System.Serializable]` to the top of the `oneTask` class. — Programmer, Feb 26 '17 at 13:01

score 0 · Answer 1 · answered Feb 26 '17 at 12:25

Somethings to fix. First you need to add [System.Serializable] on top of oneTask.

From what I can see in your JSON string you have it as an array at top level. Currently Unity JsonUtility does not support JSON array in top levels. I use this helper class to be able to use JSON top level arrays.

public class JsonHelper
{
    public static T[] getJsonArray<T>(string json)
    {
        string newJson = "{ \"array\": " + json + "}";
        Wrapper<T> wrapper = JsonUtility.FromJson<Wrapper<T>> (newJson);
        return wrapper.array;
    }

    [Serializable]
    private class Wrapper<T>
    {
        public T[] array;
    }
}

And how to use it in your case

oneTask[] objects = JsonHelper.getJsonArray<oneTask> (jsonString);

Unity C# convert String to Json array Erro

1 Answers1