在C#中實現TWIN的多線程掃描，你需要遵循以下步驟：

1. 引入必要的命名空間：

using System;
using System.Threading;
using System.Collections.Concurrent;
using System.Security.Cryptography;

2. 定義一個表示掃描結果的類：

public class ScanResult
{
    public string ImagePath { get; set; }
    public string Text { get; set; }
}

3. 創建一個TWIN設備管理器類，用于處理與TWIN設備的通信：

public class TwainDeviceManager
{
    private const int MAX_DEVICES = 10;
    private TwainDevice[] _devices;
    private Semaphore _semaphore;

    public TwainDeviceManager()
    {
        _devices = new TwainDevice[MAX_DEVICES];
        _semaphore = new Semaphore(MAX_DEVICES, true);
    }

    public void AddDevice(TwainDevice device)
    {
        _semaphore.WaitOne();
        for (int i = 0; i < MAX_DEVICES; i++)
        {
            if (_devices[i] == null)
            {
                _devices[i] = device;
                break;
            }
        }
        _semaphore.Release();
    }

    public void RemoveDevice(TwainDevice device)
    {
        _semaphore.WaitOne();
        for (int i = 0; i < MAX_DEVICES; i++)
        {
            if (_devices[i] == device)
            {
                _devices[i] = null;
                break;
            }
        }
        _semaphore.Release();
    }

    public void StartScanning()
    {
        Thread[] threads = new Thread[MAX_DEVICES];
        for (int i = 0; i < MAX_DEVICES; i++)
        {
            if (_devices[i] != null)
            {
                threads[i] = new Thread(() =>
                {
                    _devices[i].StartScanning();
                });
                threads[i].Start();
            }
        }
    }

    public void StopScanning()
    {
        for (int i = 0; i < MAX_DEVICES; i++)
        {
            if (_devices[i] != null)
            {
                _devices[i].StopScanning();
            }
        }
    }

    public ScanResult GetNextScanResult()
    {
        for (int i = 0; i < MAX_DEVICES; i++)
        {
            if (_devices[i] != null && _devices[i].HasScanResult)
            {
                ScanResult result = _devices[i].GetScanResult();
                _devices[i].ResetScanResult();
                return result;
            }
        }
        return null;
    }
}

4. 創建一個表示TWIN設備的類：

public class TwainDevice
{
    private string _name;
    private bool _isScanning;
    private ScanResult _scanResult;

    public TwainDevice(string name)
    {
        _name = name;
        _isScanning = false;
    }

    public string Name
    {
        get { return _name;