Question

如何以递归方式从文件夹中获取所有文件夹和文件树？我需要将这个树放入DataTable并从中形成一个treeView。我有一个形成递归方法的问题，现在我只有一个不能正常工作的草稿：

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Controls.Primitives;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;

namespace SWPF
{
    /// <summary>
    /// Interaction logic for MainWindow.xaml
    /// </summary>
    public partial class MainWindow : Window
    {
        private int id, parentID;
        private List<TREE> tree;
        public MainWindow()
        {
            InitializeComponent();

            tree = new List<TREE>();
            id = 0;
            parentID = 0;

            fill(@"D:\c#");
        }

        private List<TREE> fill(string path)
        {
            DirectoryInfo dir = new DirectoryInfo(path);
            foreach (DirectoryInfo folder in dir.GetDirectories())
            {
                tree.Add(new TREE(){ID = id++, ParentID = parentID++, Name = folder.Name, Type = "Folder"});

                foreach (FileInfo file in folder.GetFiles())
                {
                    tree.Add(new TREE() { ID = id, ParentID = parentID, Name = file.Name, Type = "File" });  
                }
                var p = folder.GetDirectories();
                if (p.Length > 0)
                {
                    dir = folder;
                    fill(dir.FullName);
                }
            }
            return tree;
        }
    }

public class TREE
{
    public int ID { get; set; }
    public int ParentID {get;set;}
    public string Name {get;set;}
    public string Type {get;set;}
}

}

拜托，您能告诉我正确的方法吗？将树放入DataTable。列表很好，但我需要DataTable。

我试过了，但它不想正常工作：

public DataTable fill(DirectoryInfo dir)
        {
            DataTable dt = new DataTable("Tasks");

            //dt.Columns.Add("ID");
            dt.Columns.Add("ParentID");
            dt.Columns.Add("Name");
            dt.Columns.Add("Type");

            foreach (var folder in dir.GetDirectories())
            {
                var row = dt.NewRow();

                row["ParentID"] = folder.Parent;
                row["Name"] = folder.Name;
                row["Type"] = "dir";
                dt.Rows.Add(row);

                foreach (var file in folder.GetFiles())
                {
                    var row2 = dt.NewRow();

                    row["ParentID"] = folder.Parent;
                    row["Name"] = file.Name;
                    row["Type"] = "file";
                    dt.Rows.Add(row2);
                }

                fill(folder);
            }
            return dt;
        }

Answer 1

以下是我如何实现递归部分：

static class IdGenerator
{
    static int _id = 1;
    public static int Generate() { return _id++; }
}

class Tree
{
    public int Id { get; set; }
    public string Name { get; set; }
    public int ParentId { get; set; }
    public Tree Parent { get; set; }
    public virtual ICollection<string> Files { get; set; }
    public virtual ICollection<Tree> Trees { get; set; }

    internal Tree ()
    {
        Id = IdGenerator.Generate();
        Name = String.Empty;
        ParentId = 0;
        Parent = null;
        Files = new List<string>();
        Trees = new List<Tree>();
    }

    public override string ToString()
    {
        return String.Join("\n", new[] { Id + "\t" + Path.Combine(Parent != null ? Parent.Name : String.Empty, Name) }.Union(Files).Union(Trees.Select(t => t.ToString()))) + "\n";
    }

    public static Tree CreateTree(string path, Tree parent, string pattern)
    {
        try
        {
            var tree = new Tree
            {
                Parent = parent,
                ParentId = parent != null ? parent.Id : 0,
                Name = Path.GetFileName(path),
                Files = Directory.GetFiles(path, pattern, SearchOption.TopDirectoryOnly).Select(f => Path.GetFileName(f)).ToArray(),
            };
            tree.Trees = Directory.GetDirectories(path, "*.*", SearchOption.TopDirectoryOnly).Select(d => CreateTree(d, tree, pattern)).ToArray();

            return tree;
        }
        catch (UnauthorizedAccessException)
        { return new Tree(); }
    }
}

如果我继续这样做，我会使用Entity Framework Code First从POCO Tree生成数据库，并删除静态IdGenerator，因为EF会生成这些数据库我的身份证。

修改

但是，这是如何在DataTable中完成的：

class TreeDataTable : DataTable { public TreeDataTable() : this("trees") { } public TreeDataTable(string tableName) : base(tableName) { Columns.Add("Id"); Columns.Add("Name"); Columns.Add("ParentId"); Columns.Add("Type"); } public void AddFile(int id, string name, int parent) { AddRow(id, name, parent, typeof(FileInfo)); } public void AddTree(Tree tree) { AddRow(tree.Id, tree.Name, tree.ParentId, typeof(DirectoryInfo)); var table = tree.ToDataTable(); foreach (var r in table.Rows.Cast<DataRow>()) AddRow(Convert.ToInt32(r["Id"]), r["Name"].ToString(), Convert.ToInt32(r["ParentId"]), Type.GetType(r["Type"].ToString())); } public string ToXml() { using (var sw = new StringWriter()) { using (var tw = new XmlTextWriter(sw)) { tw.Formatting = Formatting.Indented; tw.WriteStartDocument(); tw.WriteStartElement(TableName); ((IXmlSerializable)this).WriteXml(tw); tw.WriteEndElement(); tw.WriteEndDocument(); } return sw.ToString(); } } private void AddRow(int id, string name, int parent, Type type) { var row = NewRow(); row["Id"] = id; row["Name"] = name; row["ParentId"] = parent; row["Type"] = type.ToString(); Rows.Add(row); } }

并将此方法添加到Tree：

public DataTable ToDataTable() { var table = new TreeDataTable(); foreach (var f in Files) table.AddFile(IdGenerator.Generate(), f, Id); foreach (var t in Trees) table.AddTree(t); return table; }

以下是如何使用它：

class Program { static void Main(string[] args) { var path = args.FirstOrDefault(a => !String.IsNullOrEmpty(a)) ?? @"C:\Documents\Videos"; args = args.Skip(1).ToArray(); var pattern = args.FirstOrDefault(a => !String.IsNullOrEmpty(a)) ?? "*.mp4"; var tree = Tree.CreateTree(path, null, pattern); Console.WriteLine((tree.ToDataTable() as TreeDataTable).ToXml()); } }

形成一个文件和文件夹树

1 个答案: