[C#] Tree view file explorer(anul 2 facultate)

[alien]

Simple demo C# program made in college to demonstrate tree view file explorer.

Poate va ajuta pe astia care sunteti anul 2 pe la info

hg clone https://bitbucket.org/rokill3r/filetreeview

using System;
using System.Collections;
using System.Windows.Forms;
using System.Drawing;
using System.IO;

namespace cd_tree
{
    public class FileTree : TreeView
    {


        public FileTree()
        {

            GenerateImage();
            Fill();
        }
        const int HD = 0;
        const int FOLDER = 1;
        const int GLMODEL = 2;
        const int OTHERS = 3;
        protected void GenerateImage()
        {
            ImageList list = new ImageList();
            list.Images.Add(new Icon("ico/hd.ico"));
            list.Images.Add(new Icon("ico/folder.ico"));
            list.Images.Add(new Icon("ico/glmodel.ico"));
            list.Images.Add(new Icon("ico/otherfiles.ico"));

            ImageList = list;
        }
        public void Fill()
        {
            BeginUpdate();
            string[] drives = Directory.GetLogicalDrives();
            for (int i = 0; i < drives.Length; i++)
            {
                DirTreeNode dn = new DirTreeNode(drives[i]);
                dn.ImageIndex = HD;

                Nodes.Add(dn);
            }
            EndUpdate();

            // modify the tree JIT
            BeforeExpand += new TreeViewCancelEventHandler(prepare);
            AfterCollapse += new TreeViewEventHandler(clear);
            AfterCheck+=new TreeViewEventHandler(prepare_check);
        }
        public void Open(string path)
        {
            TreeNodeCollection nodes = Nodes;
            DirTreeNode subnode = null;
            int i, n;

            path = path.ToLower();
            nodes = Nodes;
            while (nodes != null)
            {
                n = nodes.Count;
                for (i = 0; i < n; i++)
                {
                    subnode = (DirTreeNode)nodes[i];
                    if (path == subnode.Path)
                    {
                        subnode.Expand();
                        return;
                    }
                    if (path.StartsWith(subnode.Path))
                    {
                        subnode.Expand();
                        break;
                    }
                }
                if (i == n)
                    return;
                nodes = subnode.Nodes;
            }
        }
        void prepare(object sender, TreeViewCancelEventArgs e)
        {
            BeginUpdate();
            DirTreeNode tn = (DirTreeNode)e.Node;
            try
            {

                tn.populate();
                EndUpdate();
            }
            catch (Exception ex)
            {
                EndUpdate();
                MessageBox.Show(ex.Message + "\n\n" + ex.StackTrace,
                                "Problems");
            }
        }
        void prepare_check(object sender, TreeViewEventArgs e)
        {
            BeginUpdate();
            DirTreeNode tn = (DirTreeNode)e.Node;
            try
            {
                tn.Expand();
                tn.populate();
                EndUpdate();
            }
            catch (Exception ex)
            {
                EndUpdate();
                MessageBox.Show(ex.Message + "\n\n" + ex.StackTrace,
                                "Problems");
            }
        }
        void clear(object sender, TreeViewEventArgs e)
        {
            BeginUpdate();
            DirTreeNode tn = (DirTreeNode)e.Node;
            tn.setLeaf(true);
            EndUpdate();
        }

        public class DirTreeNode : TreeNode
        {
            string path;
            int type;
            public virtual string Path { get { return path; } }

            public DirTreeNode(string s)
                : base(s)
            {
                path = s.ToLower();
                setLeaf(true);
                type = HD;
                ImageIndex = type;
                SelectedImageIndex = type;
            }
            DirTreeNode(string s, int aType)
                : base(new FileInfo(s).Name)
            {
                path = s.ToLower();
                type = aType;
                ImageIndex = type;
                SelectedImageIndex = type;
                if (type == FOLDER || type == GLMODEL)
                    setLeaf(true);
            }

            public bool IsSpecialFile(string s)
            {
                if (!s.EndsWith(".dll"))
                    return false;
                ImageIndex = GLMODEL;
                return true;
            }

            internal void populate()
            {
                if (type != FOLDER && type != HD)
                    return;
                ArrayList folder = new ArrayList();
                ArrayList special = new ArrayList();
                ArrayList other = new ArrayList();

                string[] files = Directory.GetFileSystemEntries(Path);
                for (int i = 0; i < files.Length; i++)
                {
                    FileAttributes fa = File.GetAttributes(files[i]);
                    if ((fa & FileAttributes.Directory) != 0)
                        folder.Add(new DirTreeNode(files[i], FOLDER));
                    else
                    {
                        if (IsSpecialFile(files[i]))
                            special.Add(new DirTreeNode(files[i], GLMODEL));
                        else
                            other.Add(new DirTreeNode(files[i], OTHERS));
                    }
                }
                bool ischecked = false;
                if (this.Checked == true)
                    ischecked = true;
                // add the node
                Nodes.Clear();
                foreach (DirTreeNode dtn in folder)
                {
                    if (ischecked)
                        dtn.Checked = true;
                    Nodes.Add(dtn);
                }
                foreach (DirTreeNode dtn in special)
                {
                    if (ischecked)
                        dtn.Checked = true;
                    Nodes.Add(dtn);
                }
                foreach (DirTreeNode dtn in other)
                {
                    if (ischecked)
                        dtn.Checked = true;
                    Nodes.Add(dtn);
                }

                ImageIndex = type; 
            }

            bool isLeaf = true;
            internal void setLeaf(bool 
            {
                ImageIndex = type; 
                Nodes.Clear();
                isLeaf = b;
                if (IsExpanded)
                    return;
                if (!isLeaf)
                    return;
                Nodes.Add(new TreeNode());
            }
        }
    }




    static class Program
    {
        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            Application.EnableVisualStyles();
            Application.SetCompatibleTextRenderingDefault(false);


            Application.Run(new Form1());
        }
    }
}