Creating tree view dynamically according to json text in Winforms

Question

I am building an application that gets in run-time JSON message from external source.

I don\'t know anything about the structure of the message text.

I want

Answer 1

This code will handle both JArray or JObject as an input:

        string jsonString = "your json string here";
        string rootName = "root", nodeName = "node";
        JContainer json;
        try {
            if (jsonString.StartsWith("["))
            {
                json = JArray.Parse(jsonString);
                treeView1.Nodes.Add(Utilities.Json2Tree((JArray)json, rootName, nodeName));
            }
            else
            {
                json = JObject.Parse(jsonString);
                treeView1.Nodes.Add(Utilities.Json2Tree((JObject)json, text));
            }
        }
        catch(JsonReaderException jre)
        {
            MessageBox.Show("Invalid Json.");
        }

public class Utilities
{

    public static TreeNode Json2Tree(JArray root, string rootName = "", string nodeName="")
    {
        TreeNode parent = new TreeNode(rootName);
        int index = 0;

        foreach(JToken obj in root)
        {
            TreeNode child = new TreeNode(string.Format("{0}[{1}]", nodeName, index++));
            foreach (KeyValuePair token in (JObject)obj)
            {
                switch (token.Value.Type)
                {
                    case JTokenType.Array:
                    case JTokenType.Object:
                        child.Nodes.Add(Json2Tree((JObject)token.Value, token.Key));
                        break;
                    default:
                        child.Nodes.Add(GetChild(token));
                        break;
                }
            }
            parent.Nodes.Add(child);
        }

        return parent;
    }

    public static TreeNode Json2Tree(JObject root, string text = "")
    {
        TreeNode parent = new TreeNode(text);

        foreach (KeyValuePair token in root)
        {

            switch (token.Value.Type)
            {
                case JTokenType.Object:
                    parent.Nodes.Add(Json2Tree((JObject)token.Value, token.Key));
                    break;
                case JTokenType.Array:
                    int index = 0;
                    foreach(JToken element in (JArray)token.Value)
                    {
                        parent.Nodes.Add(Json2Tree((JObject)element, string.Format("{0}[{1}]", token.Key, index++)));
                    }

                    if (index == 0) parent.Nodes.Add(string.Format("{0}[ ]", token.Key)); //to handle empty arrays
                    break;
                default:
                    parent.Nodes.Add(GetChild(token));
                    break;
            }
        }

        return parent;
    }

    private static TreeNode GetChild(KeyValuePair token)
    {
        TreeNode child = new TreeNode(token.Key);
        child.Nodes.Add(string.IsNullOrEmpty(token.Value.ToString()) ? "n/a" : token.Value.ToString());
        return child;
    }

}