基于阻塞队列的生产者消费者C#并发设计

static void Main(string[] args)
{
ProcessQueue<int> processQueue = new ProcessQueue<int>();
processQueue.ProcessExceptionEvent += ProcessQueue_ProcessExceptionEvent;
processQueue.ProcessItemEvent += ProcessQueue_ProcessItemEvent;

for (int i = 0; i < 50; i++)
{
processQueue.Enqueue(i);
}

Console.WriteLine("阻塞队列的数量: {0}", processQueue.GetInternalItemCount());

processQueue.Flush();

Console.Read();
}

/// <summary>
/// 该方法对入队的每个元素进行处理
/// </summary>
/// <param name="value"></param>
private static void ProcessQueue_ProcessItemEvent(int value)
{
Console.WriteLine("输出: {0}", value);
}

/// <summary>
///  处理异常
/// </summary>
/// <param name="obj">队列实例</param>
/// <param name="ex">异常对象</param>
/// <param name="value">出错的数据</param>
private static void ProcessQueue_ProcessExceptionEvent(dynamic obj, Exception ex, int value)
{
Console.WriteLine(ex.ToString());
}

public class ProcessQueue<T>
{
private BlockingCollection<T> _queue;
private CancellationTokenSource _cancellationTokenSource;
private CancellationToken _cancellToken;
//内部线程池
private List<Thread> _threadCollection;

//队列是否正在处理数据
private int _isProcessing;
//有线程正在处理数据
private const int Processing = 1;
//没有线程处理数据
private const int UnProcessing = 0;
//队列是否可用   单个线程下用while来判断，多个线程下用if判断，随后while循环队列的数量
private volatile bool _enabled = true;
//内部处理线程数量
private int _internalThreadCount;
// 消费者处理事件
public event Action<T> ProcessItemEvent;
//处理异常，需要三个参数，当前队列实例，异常，当时处理的数据
public event Action<dynamic, Exception, T> ProcessExceptionEvent;

public ProcessQueue()
{
_queue = new BlockingCollection<T>();
_cancellationTokenSource = new CancellationTokenSource();
_internalThreadCount = 3;
_cancellToken = _cancellationTokenSource.Token;
_threadCollection = new List<Thread>();
}

public ProcessQueue(int internalThreadCount) : this()
{
this._internalThreadCount = internalThreadCount;
}

/// <summary>
/// 队列内部元素的数量
/// </summary>
public int GetInternalItemCount()
{
//return _queue.Count;
return _threadCollection.Count;
}
//生产者生产
public void Enqueue(T items)
{
if (items == null)
{
throw new ArgumentException("items");
}

_queue.Add(items);
DataAdded();
}

public void Flush()
{
StopProcess();

while (_queue.Count != 0)
{
T item = default(T);
if (_queue.TryTake(out item))
{
try
{
ProcessItemEvent(item);
}
catch (Exception ex)
{
OnProcessException(ex, item);
}
}
}
}
// 通知消费者消费队列元素
private void DataAdded()
{
if (_enabled)
{
if (!IsProcessingItem())
{
Console.WriteLine("DataAdded");
ProcessRangeItem();
StartProcess();
}
}
}

//判断是否队列有线程正在处理
private bool IsProcessingItem()
{
// 替换第一个参数, 如果相等
//int x = Interlocked.CompareExchange(ref _isProcessing, Processing, UnProcessing);
return !(Interlocked.CompareExchange(ref _isProcessing, Processing, UnProcessing) == UnProcessing);
}
// 多消费者消费
private void ProcessRangeItem()
{
for (int i = 0; i < this._internalThreadCount; i++)
{
ProcessItem();
}
}
// 开启消费处理
private void ProcessItem()
{
Thread currentThread = new Thread((state) =>
{
T item = default(T);
while (_enabled)
{
try
{
try
{
if (!_queue.TryTake(out item))
{
//Console.WriteLine("阻塞队列为0时的item: {0}", item);
//Console.WriteLine("ok!!!");
break;
}
// 处理事件
ProcessItemEvent(item);
}
catch (OperationCanceledException ex)
{
DebugHelper.DebugView(ex.ToString());
}

}
catch (Exception ex)
{
OnProcessException(ex, item);
}
}
});
_threadCollection.Add(currentThread);
}
// 开启消费者
private void StartProcess()
{
//Console.WriteLine("线程的数量: {0}", _threadCollection.Count);
foreach (var thread in _threadCollection)
{
thread.Start();
thread.IsBackground = true;
}
}
// 终止运行
private void StopProcess()
{
this._enabled = false;
foreach (var thread in _threadCollection)
{
if (thread.IsAlive)
{
thread.Join();
}
}
_threadCollection.Clear();
}

private void OnProcessException(Exception ex, T item)
{
var tempException = ProcessExceptionEvent;
Interlocked.CompareExchange(ref ProcessExceptionEvent, null, null);

if (tempException != null)
{
ProcessExceptionEvent(this, ex, item);
}
}

}