适用于 .NET 的线程安全缓冲区

(注意：虽然我想为.Net 4.0的未来提供想法，但我仅限于该项目的.Net 3.5。

我有一个线程，它从外部设备异步读取数据(在代码示例中由如此富有创意的 strSomeData 模拟：-(并将其存储在 StringBuilder 'buffer' (strBuilderBuffer ：-(

在"主代码"中，我想"啃"这个"缓冲区"。 但是，从"操作"的角度来看，我不确定如何以线程安全的方式执行此操作。 我知道从"数据"的角度来看它是安全的，因为根据 msdn，"这种(StringBuilder(类型的任何公共静态成员都是线程安全的。任何实例成员都不保证是线程安全的。 但是，我下面的代码说明，从"操作"的角度来看，它可能不是线程安全的。

关键是我担心代码的两行：

string strCurrentBuffer = ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.ToString();
// Thread 'randomly' slept due to 'inconvenient' comp resource scheduling...
ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.Length = 0;

如果计算机操作系统在缓冲区的"读取"和缓冲区的"清除"之间使我的线程休眠，我可能会丢失数据(这很糟糕：-(

有没有办法保证这两行的"原子性"并迫使计算机不要中断它们？

关于下面弗拉德关于使用lock的建议，我试过了，但它没有用(真的(：

    public void BufferAnalyze()
    {
        String strCurrentBuffer;
        lock (ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer)
        {
            strCurrentBuffer = ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.ToString();
            Console.WriteLine("[BufferAnalyze()]  ||<<  Thread 'Randomly' Slept due to comp resource scheduling");
            Thread.Sleep(1000);  //  Simulate poor timing of thread resourcing...
            ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.Length = 0;
        }
        Console.WriteLine("[BufferAnalyze()]'r'nstrCurrentBuffer[{0}] == {1}", strCurrentBuffer.Length.ToString(), strCurrentBuffer);
    }

有没有更好的方法来实现线程安全缓冲区？

以下是完整代码：

namespace ExploringThreads
{
    /// <summary>
    /// Description of BasicThreads_TestThreadSafety_v1a
    /// </summary>
    class ThreadWorker_TestThreadSafety_v1a
    {
        private Thread thread;
        public static StringBuilder strBuilderBuffer = new StringBuilder("", 7500);
        public static StringBuilder strBuilderLog = new StringBuilder("", 7500);
        public bool IsAlive
        {
            get { return thread.IsAlive; }
        }
        public ThreadWorker_TestThreadSafety_v1a(string strThreadName)
        {
            // It is possible to have a thread begin execution as soon as it is created.
            // In the case of MyThread this is done by instantiating a Thread object inside MyThread's constructor.
            thread = new Thread(new ThreadStart(this.threadRunMethod));
            thread.Name = strThreadName;
            thread.Start();
        }
        public ThreadWorker_TestThreadSafety_v1a() : this("")
        {
            //   NOTE:  constructor overloading ^|^
        }
        //Entry point of thread.
        public void threadRunMethod()
        {
            Console.WriteLine("[ThreadWorker_TestThreadSafety_v1a threadRunMethod()]");
            Console.WriteLine(thread.Name + " starting.");
            int intSomeCounter = 0;
            string strSomeData = "";
            do
            {
                Console.WriteLine("[ThreadWorker_TestThreadSafety_v1a threadRunMethod()] running.");
                intSomeCounter++;
                strSomeData = "abcdef" + intSomeCounter.ToString() + "|||";
                strBuilderBuffer.Append(strSomeData);
                strBuilderLog.Append(strSomeData);
                Thread.Sleep(200);
            } while(intSomeCounter < 15);
            Console.WriteLine(thread.Name + " terminating.");
        }
    }
    /// <summary>
    /// Description of BasicThreads_TestThreadSafety_v1a.
    /// </summary>
    public class BasicThreads_TestThreadSafety_v1a
    {
        public BasicThreads_TestThreadSafety_v1a()
        {
        }
        public void BufferAnalyze()
        {
            string strCurrentBuffer = ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.ToString();
            Console.WriteLine("[BufferAnalyze()]  ||<<  Thread 'Randomly' Slept due to comp resource scheduling");
            Thread.Sleep(1000);  //  Simulate poor timing of thread resourcing...
            ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.Length = 0;
            Console.WriteLine("[BufferAnalyze()]'r'nstrCurrentBuffer[{0}] == {1}", strCurrentBuffer.Length.ToString(), strCurrentBuffer);
        }
        public void TestBasicThreads_TestThreadSafety_v1a()
        {
            Console.Write("Starting TestBasicThreads_TestThreadSafety_v1a  >>>  Press any key to continue . . . ");
            Console.Read();
            // First, construct a MyThread object.
            ThreadWorker_TestThreadSafety_v1a threadWorker_TestThreadSafety_v1a = new ThreadWorker_TestThreadSafety_v1a("threadWorker_TestThreadSafety_v1a Child");
            do
            {
                Console.WriteLine("[TestBasicThreads_TestThreadSafety_v1a()]");
                Thread.Sleep(750);
                BufferAnalyze();
                //} while (ThreadWorker_TestThreadSafety_v1a.thread.IsAlive);
            } while (threadWorker_TestThreadSafety_v1a.IsAlive);
            BufferAnalyze();
            Thread.Sleep(1250);
            Console.WriteLine("[TestBasicThreads_TestThreadSafety_v1a()]");
            Console.WriteLine("ThreadWorker_TestThreadSafety_v1a.strBuilderLog[{0}] == {1}", ThreadWorker_TestThreadSafety_v1a.strBuilderLog.Length.ToString(), ThreadWorker_TestThreadSafety_v1a.strBuilderLog);
            Console.Write("Completed TestBasicThreads_TestThreadSafety_v1a  >>>  Press any key to continue . . . ");
            Console.Read();
        }
    }
}

public class Example
{
  private BlockingCollection<string> buffer = new BlockingCollection<string>();
  public Example()
  {
    new Thread(ReadFromExternalDevice).Start();
    new Thread(BufferAnalyze).Start();
  }
  private void ReadFromExteneralDevice()
  {
    while (true)
    {
      string data = GetFromExternalDevice();
      buffer.Add(data);
      Thread.Sleep(200);
    }
  }
  private void BufferAnalyze()
  {
    while (true)
    {
      string data = buffer.Take(); // This blocks if nothing is in the queue.
      Console.WriteLine(data);
    }
  } 
}

public static StringBuilder strBuilderBuffer = new StringBuilder("", 7500);
private object BufferLock = new object();
...
lock (BufferLock)
    strBuilderBuffer.Append(strSomeData);
...
string strCurrentBuffer;
lock (BufferLock)
{
    strCurrentBuffer = ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.ToString();
    ThreadWorker_TestThreadSafety_v1a.strBuilderBuffer.Clear();
}
Console.WriteLine("[BufferAnalyze()]  ||<<  Thread 'Randomly' Slept ...");
Thread.Sleep(1000);  //  Simulate poor timing of thread resourcing...