按照个数分组目录里面的文件

直接上效果图和代码：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Forms;

namespace ProcessItems
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();

            // 启用拖放
            treeViewItems.AllowDrop = true;

            // 拖放进入事件
            treeViewItems.DragEnter += new DragEventHandler(treeView_DragEnter);

            // 拖放事件
            treeViewItems.DragDrop += new DragEventHandler(treeView_DragDrop);

            // 设置窗体启动时居中显示
            this.StartPosition = FormStartPosition.CenterScreen;
        }

        // 允许拖放的文件类型
        private void treeView_DragEnter(object sender, DragEventArgs e)
        {
            if (e.Data.GetDataPresent(DataFormats.FileDrop))
            {
                e.Effect = DragDropEffects.Copy; // 或者其他效果
            }
            else
            {
                e.Effect = DragDropEffects.None;
            }
        }

        // 处理拖放事件
        private void treeView_DragDrop(object sender, DragEventArgs e)
        {
            string[] files = (string[])e.Data.GetData(DataFormats.FileDrop);
            foreach (string file in files)
            {
                // 检查文件是否存在
                if (/*File.Exists(file) || */Directory.Exists(file))
                {
                    // 在这里添加文件到TreeView的逻辑
                    treeViewItems.Nodes.Add(new TreeNode(file));
                }
            }
        }
        private void buttonOK_Click(object sender, EventArgs e)
        {
            foreach (var dir in treeViewItems.Nodes)
            {
                TreeNode node = dir as TreeNode;

                string stCurDir = node.Text;

                MoveFilesToSplitDirectories(stCurDir, Convert.ToInt32(numCountLimit.Value), false);
            }

            MessageBox.Show("处理完成!", "提示！", MessageBoxButtons.OK, MessageBoxIcon.Information);
        }

        static bool MoveFilesToSplitDirectories(string directoryPath, int filesPerDirectory, bool includeSubdirectories)
        {
            if (!Directory.Exists(directoryPath))
            {
                Console.WriteLine("The specified directory does not exist.");
                return false;
            }

            var files = new List<string>();

            // Get files from the directory and optionally its subdirectories
            if (includeSubdirectories)
            {
                files.AddRange(Directory.GetFiles(directoryPath, "*", SearchOption.AllDirectories));
            }
            else
            {
                files.AddRange(Directory.GetFiles(directoryPath));
            }

            if (files.Count == 0)
            {
                Console.WriteLine("No files found in the directory.");
                return false;
            }

            string directoryName = new DirectoryInfo(directoryPath).Name;
            string parentDirectoryPath = Directory.GetParent(directoryPath).FullName;

            int directoryCounter = 1;
            int fileCounter = 0;

            string currentDestDir = Path.Combine(parentDirectoryPath, $"{directoryName}{directoryCounter}");
            Directory.CreateDirectory(currentDestDir);

            foreach (var file in files)
            {
                if (fileCounter >= filesPerDirectory)
                {
                    directoryCounter++;
                    fileCounter = 0;
                    currentDestDir = Path.Combine(parentDirectoryPath, $"{directoryName}{directoryCounter}");
                    Directory.CreateDirectory(currentDestDir);
                }

                string destFile = Path.Combine(currentDestDir, Path.GetFileName(file));
                File.Move(file, destFile);
                fileCounter++;
            }

            return true;
        }
    }
}