Converting tree view to byte[], then back again

Question

I'm trying to convert a treeview to a byte array and then back again. So far when the form loads, it will load the structure of my documents. Then as far as I know, it will convert it to a byte array and back but I'm not sure how to convert the byte array back to the tree view.

Here is my code:

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    private void Form1_Load(object sender, EventArgs e)
    {
        string filepath = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments);
        ListDirectory(treeView1, filepath);
    }

    private static void ListDirectory(TreeView treeView, string path)
    {
        treeView.Nodes.Clear();

        var stack = new Stack<TreeNode>();
        var rootDirectory = new DirectoryInfo(path);
        var node = new TreeNode(rootDirectory.Name) { Tag = rootDirectory };
        stack.Push(node);

        while (stack.Count > 0)
        {
            var currentNode = stack.Pop();
            var directoryInfo = (DirectoryInfo)currentNode.Tag;

            foreach (var directory in directoryInfo.GetDirectories())
            {
                var childDirectoryNode = new TreeNode(directory.Name) { Tag = directory };
                currentNode.Nodes.Add(childDirectoryNode);
                stack.Push(childDirectoryNode);
            }

            foreach (var file in directoryInfo.GetFiles())
                currentNode.Nodes.Add(new TreeNode(file.Name));
        }

        treeView.Nodes.Add(node);
    }

    private Byte[] SerilizeQueryFilters()
    {
        BinaryFormatter bf = new BinaryFormatter();

        List<TreeNode> list = new List<TreeNode>();

        foreach(TreeNode node in treeView1.Nodes)
        {
            list.Add(node);
        }

        using (MemoryStream ms = new MemoryStream())
        {
            bf.Serialize(ms, list);
            return ms.GetBuffer();
        }
    }

    private void DeSerilizeQueryFilters(byte[] items)
    {
        BinaryFormatter bf = new BinaryFormatter();

        try
        {
            using (MemoryStream ms = new MemoryStream())
            {
                ms.Write(items, 0, items.Length);
                ms.Position = 0;
                _list = bf.Deserialize(ms) as List<TreeNode>;
                treeView2.Nodes.AddRange(_list.ToArray());
            }
        }
        catch(Exception e)
        { 
            Console.WriteLine(e.StackTrace);
        }
    }

    private void button1_Click(object sender, EventArgs e)
    {
        byte[] data = SerilizeQueryFilters();
        DeSerilizeQueryFilters(data);
    }
}

So the bit that's throwing an error at the moment is

_list = bf.Deserialize(ms) as List<TreeNode>;

and I get this error:

System.Runtime.Serialization.SerializationException

Does anyone have any ideas?

Answer 1

The solution was easy using the recommendation of @Fildor I stop using BinaryFormatter and now I use JSON and using the recommendation of @madreflection I create a custom class to save the data of the TreeNode.

Custom TreeNode Class

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace TreeViewStuff
{
    public class Node
    {
        public int id;
        public string text = "";
        public int parentId = 0;
        public bool cheked = false;
    }
}

Deserialize/Serialize TreeView Class

using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.CompilerServices;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace TreeViewStuff
{
    public class TreeviewPersist
    {

        public static string strJson;
        private static TreeView treeView_;

        static public string ToJson(TreeView treeView)
        {
            List<Node> nodes = new List<Node>();

            foreach(TreeNode node in treeView.Nodes) 
            {
                SerializeTree(nodes, node);
            }

            nodes.RemoveAt(0);

            return JsonConvert.SerializeObject(nodes);
        }

        public delegate void FunctionDelegate();

        public static void FromJson(string strJson_, TreeView treeView)
        {
            strJson = strJson_;
            treeView_ = treeView;

            treeView.BeginInvoke(new FunctionDelegate(FromJson));
        }

        private static void FromJson()
        {
            treeView_.Nodes.Clear();

            List<Node> nodes = JsonConvert.DeserializeObject<List<Node>>(strJson);

            foreach(Node node in nodes)
            {
                if (node.parentId == 0)
                {
                    TreeNode treeNode = treeView_.Nodes.Add(node.text);
                    treeNode.Name = $"{node.id}";
                    treeNode.Checked = node.cheked;
                }
                else
                {
                    TreeNode[] foundNodes = treeView_.Nodes.Find($"{node.parentId}", true);
                    if (foundNodes.Length > 0)
                    {
                        TreeNode treeNode = foundNodes[0].Nodes.Add(node.text);
                        treeNode.Checked = node.cheked;
                        treeNode.Name = $"{node.id}";
                    }
                }
            }
        }

        static private void SerializeTree(List<Node> nodes, TreeNode treeNode)
        {
            Node node = new Node();

            bool suces = Int32.TryParse(treeNode.Name, out node.id);

            TreeNode parent = treeNode.Parent;
            if (parent != null)
            {
                suces = Int32.TryParse(parent.Name, out node.parentId);
            }
            else
            {
                node.parentId = 0;
            }

            node.text = treeNode.Text;
            node.cheked = treeNode.Checked;

            nodes.Add(node);

            foreach (TreeNode tn in treeNode.Nodes)
            {
                SerializeTree(nodes, tn);
            }
        }
    }
}

Directories/Files to TreeView Method

private static void ListDirectory(TreeView treeView, string path)
{
    treeView.Nodes.Clear();

    int id = 1;

    var stack = new Stack<TreeNode>();
    var rootDirectory = new DirectoryInfo(path);
    var node = new TreeNode(rootDirectory.Name) { Tag = rootDirectory };
    stack.Push(node);

    while (stack.Count > 0)
    {
        var currentNode = stack.Pop();
        var directoryInfo = (DirectoryInfo)currentNode.Tag;
        foreach (var directory in directoryInfo.GetDirectories())
        {
            var childDirectoryNode = new TreeNode(directory.Name) { Tag = directory };
            childDirectoryNode.Name = $"{id++}";
            currentNode.Nodes.Add(childDirectoryNode);
            stack.Push(childDirectoryNode);
        }
        foreach (var file in directoryInfo.GetFiles())
        {
            TreeNode treeNode = new TreeNode(file.Name);
            treeNode.Name = $"{id++}";
            currentNode.Nodes.Add(new TreeNode(file.Name));
        }

    }

    treeView.Nodes.Add(node);
}

To make this work each TreeNode needs to have a Unique Id that is going to be saved in the name of the TreeNode as I do in the Directories/Files to TreeView Method. Thanks @Fildor and @madreflection for your help!