Parsing JSON API in C#

Question

so I'm fairly new to programming but am looking to go much deeper with it. I recently started to get involved in a project to create a WinForm program for a website that uses an API system in JSON.

I've never used an API before so I'm not quite sure how it works but after looking at it for a few minutes I seem to have the gist of it. What I don't get is how exactly parsing JSON in C# works.

I found this link after a little google searching. And I got it working (somewhat) with this code.

static void Main(string[] args)
{
        WebClient c = new WebClient();
        var vLogin = c.DownloadString("https://www.openraid.us/index.php/api/login/username/password");
        //Returns string 
        //{"status":1,"error":null,"token":"250-1336515541-c48d354d96e06d488d1a2530071ef07c9532da26"} 
        //Token = random, no decisive length*/
        JObject o = JObject.Parse(vLogin);
        Console.WriteLine("Login Status: " + o["status"]);
        String sToken = "" + o["token"];
        Console.WriteLine(sToken);
        Console.WriteLine("");
        //Breaks after this
        var myRaids = c.DownloadString("https://www.openraid.us/index.php/api/myraids/"+sToken);
        JObject r = JObject.Parse(myRaids); //error occurs here
        String sEventId = "" + r["event_id"];
        Console.WriteLine("Event ID: " + sEventId);
        Console.ReadLine();
}

So to me it looks like I have parsing 1 page done and handled, but when I move onto the second I get this error.

Error reading JObject from JsonReader. Current JsonReader item is not an object: StartArray. Path '', line 1, position 1.

So I guess my question is, how do I parse more than 1 page or call of JSON and what would be the easiest way to break up each section of the JSON object (Such as status, error, and token, into C# strings?

Solution 1

Did you try to JArray instead? Depending on what kind of object you are trying to return

WebClient client = new WebClient();
var data = client.DownloadString("");
var jArray = JArray.Parse(data);

Solution 2

JSON requires brackets for arrays and commas between multiple objects.

This is per the JSON standard. I also recommend using JSON.net via NuGet instead of the native JSON parser unless it is overkill and you cannot have the extra bloat.

For example, your parsing a file with two seperate JSON objects - the following does not work per the JSON standard (lacks a comma between the 2 objects and the two objects are not encapsulated by brackets):

{"status":1,"error":null}
{"status":2,"error":null}

The following 3 JSON objects parsed from a file does work (has brackets for multiple objects and commas between objects):

[{"glossary": {"title": "fun glossary","SeeAlso": ["GML", "XML"]},
{"glossary": {"title": "grey glossary","SeeAlso": ["GML", "XML"]},
{"glossary": {"title": "blue glossary","SeeAlso": ["GML", "XML"]}]

Comments

[Jonno]

+1 it's probably in the doco somewhere but one would expect the JSON.Net API is a bit more intuitive... thanks for this answer :-)