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Ninject disposes child object before disposing the parent that uses it

When I call IKernel.Dispose() in the [TestCleanup] method of my DataTest, my application is crashing because the first object to be disposed is still in use by another object.
This code reproduces the issue:
using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using Ninject;
using Ninject.Modules;
[TestClass]
public class NinjectDisposeIssue
{
private IKernel kernel;
[TestInitialize]
public void TestInitialize()
{
kernel = new StandardKernel(new Module());
}
[TestCleanup]
public void TestCleanup()
{
kernel.Dispose();
}
[DataTestMethod]
[DataRow]
[DataRow]
public void DataTestMethod()
{
var parent = kernel.Get<Parent>();
parent.Run();
}
}
public class Module : NinjectModule
{
public override void Load()
{
Bind<Parent>().ToSelf().InSingletonScope();
Bind<Service>().ToSelf().InSingletonScope();
Bind<Database>().ToSelf().InSingletonScope();
// create 2 workers
Bind<Worker>().ToSelf().InSingletonScope();
Bind<Worker>().ToSelf().InSingletonScope();
}
}
public class Parent
{
private readonly Service service;
private readonly IEnumerable<Worker> workers;
public Parent(Service service, IEnumerable<Worker> workers)
{
this.service = service;
this.workers = workers;
}
public void Run()
{
for (var i = 0; i < 2; i++)
{
foreach (var worker in workers)
{
worker.StartWork();
}
service.DoSomething();
}
}
}
public class Service
{
private readonly Database database;
public Service(Database database)
{
this.database = database;
}
public void DoSomething()
{
var value = database.Get();
// do something with the value
}
}
public class Worker : IDisposable
{
private readonly Database database;
private Task workTask;
private CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
private bool disposedValue;
public Worker(Database database)
{
this.database = database;
}
public void StartWork()
{
if (workTask == null)
{
workTask = Task.Run(WorkLoop);
}
}
private void WorkLoop()
{
while (!cancellationTokenSource.Token.IsCancellationRequested)
{
var value = database.Get();
// do some work with the value...
}
}
protected virtual void Dispose(bool disposing)
{
if (!disposedValue)
{
if (disposing)
{
cancellationTokenSource.Cancel();
workTask.Wait();
workTask.Dispose();
}
disposedValue = true;
}
}
public void Dispose()
{
Dispose(disposing: true);
GC.SuppressFinalize(this);
}
}
public class Database : IDisposable
{
private readonly ThirdPartyDb thirdPartyDb = new ThirdPartyDb();
private bool disposedValue;
public string Get()
{
return thirdPartyDb.Get("foo");
}
protected virtual void Dispose(bool disposing)
{
if (!disposedValue)
{
if (disposing)
{
thirdPartyDb.Dispose();
}
disposedValue = true;
}
}
public void Dispose()
{
Dispose(disposing: true);
GC.SuppressFinalize(this);
}
}
public class ThirdPartyDb : IDisposable
{
private bool isDisposed = false;
public void Dispose()
{
isDisposed = true;
}
public string Get(string key)
{
if (isDisposed)
{
throw new ObjectDisposedException(nameof(ThirdPartyDb));
}
return "bar";
}
}
The Dispose() method of the Database object is being called before the Dispose() method of the 2 Workers.
Question: Is there something I can do in the bindings to force the Workers to be disposed before the Database or is the way I have this configured fundamentally wrong?

As a simple solution, you can just add another CancellationTokenSource to your Database. This way you'll make sure that the thirdPartyDb is not getting called after disposal.
public class Database : IDisposable
{
private CancellationTokenSource cancellationTokenSource = new CancellationTokenSource();
private readonly ThirdPartyDb thirdPartyDb = new ThirdPartyDb();
private bool disposedValue;
public string Get()
{
if (cancellationTokenSource.Token.IsCancellationRequested) return ""; //Return anything acceptable for you
return thirdPartyDb.Get("foo");
}
protected virtual void Dispose(bool disposing)
{
if (!disposedValue)
{
if (disposing)
{
cancellationTokenSource.Cancel();
thirdPartyDb.Dispose();
}
disposedValue = true;
}
}
public void Dispose()
{
Dispose(disposing: true);
GC.SuppressFinalize(this);
}
}

How to skip/pause notifications sent to observers in c#

I implemented an observer pattern using events and delegates. The program is receiving and processing big amounts of data (around 3000 messages per second) but at some point, it starts sending messages with a delayed timestamp, which I am trying to fix. I have 3 main classes that do the job in my opinion:
public class MessageTracker : IObservable<MessageEventArgs>
{
private List<IObserver<MessageEventArgs>> observers;
public MessageTracker()
{
observers = new List<IObserver<MessageEventArgs>>();
}
private static readonly MessageTracker mInstance = new MessageTracker();
private static MessageTracker getInstance() => mInstance;
private class Unsubscriber : IDisposable
{
private List<IObserver<MessageEventArgs>> _observers;
private IObserver<MessageEventArgs> _observer;
public Unsubscriber(List<IObserver<MessageEventArgs>> observers, IObserver<MessageEventArgs> observer)
{
this._observers = observers;
this._observer = observer;
}
public void Dispose()
{
if (! (_observer == null)) _observers.Remove(_observer);
}
}
public IDisposable Subscribe(IObserver<MessageEventArgs> observer)
{
if (! observers.Contains(observer))
observers.Add(observer);
return new Unsubscriber(observers, observer);
}
public void MessageTrack(MessageEventArgs msg) {
observers.AsParallel().ForAll(observer =>
{
if (msg is null)
observer.OnError(new ArgumentException("MessageError."));
else
observer.OnNext(msg);
});
}
public void EndMessageTrans(){
foreach(var observer in observers.ToArray())
if (observers.Contains(observer))
observer.OnCompleted();
observers.Clear();
}
}
public class MessageReporter : IObserver<MessageEventArgs>
{
private IDisposable unsubscriber;
public MessageReporter()
{ }
public event EventHandler<MessageEventArgs> OnNextMessage;
public virtual void Subscribe(IObservable<MessageEventArgs> provider)
{
if (provider != null)
unsubscriber = provider.Subscribe(this);
}
public void OnCompleted()
{
this.Unsubscribe();
}
public void OnError(Exception error)
{
}
public void OnNext(MessageEventArgs value)
{
if (OnNextMessage != null)
{
OnNextMessage?.Invoke(this, value);
}
}
public virtual void Unsubscribe()
{
unsubscriber.Dispose();
}
}
public sealed class MessageDataWorker
{
private readonly bool mSubscribeAll;
private readonly IEnumerable<string> mMessages;
public MessageDataWorker(IEnumerable<string> messages)
{
mMessages = messages;
if ((mMessages?.Count() ?? 0) == 0)
mSubscribeAll = true;
}
public override void DoWork()
{
var messageReporter = new MessageReporter();
messageReporter.OnNextMessage += OnNewMessageReceived;
messageReporter.Subscribe(MessageTracker.GetInstance());
while (!mShouldStop.WaitOne(100)) ;
MessageReporter.Unsubscribe();
}
private void OnNewMessageReceived(object sender, MessageEventArgs e)
{
if (!mSubscribeAll && !mMessages.Contains(e.Message))
return;
string message = "Message|" +
$"{e.Time}|" +
$"{e.Text};
try
{
Console.WriteLine(message);
}
catch { }
}
}
What I am trying to achieve is skipping notifications or receiving data for X milliseconds after sending the last message and afterward send the newest received message. I tried sleeping the observers and the provider but it just increased the delay. I think I am missing something and any suggestion would be appreciated.

From what I can tell from your code you could write the three classes with this code:
var messageTrack = new Subject<MessageEventArgs>();
var query =
from e in messageTrack
where !mMessages.Contains(e.Message)
select $"Message|{e.Time}|{e.Text}";
query.Throttle(TimeSpan.FromMilliseconds(X)).Subscribe(Console.WriteLine);
You should never need to implement IObservable<> or IObserver<> yourself. It almost always ends in disaster.
The above code handles the throttling you wanted.

Static class / Object? How to dispose

i'm really struggeling with OOP. I would like to start a process in my additional class. The process is a shell and I need to access this shell from severel forms and classes to write the commands and to receive the output. I use events to get the data. Here is my class for the process.
My class for the
public class ADBShell
{
public static string output = String.Empty;
public static Process adbshell = new Process();
public void Start_ADBShell()
{
if (adbshell != null && !adbshell.HasExited)
return;
adbshell = new Process();
adbshell.StartInfo.UseShellExecute = false;
adbshell.StartInfo.FileName = #"D:\adb\adb.exe";
adbshell.StartInfo.Arguments = "shell";
adbshell.StartInfo.RedirectStandardOutput = true;
adbshell.StartInfo.RedirectStandardInput = true;
//adb.StartInfo.RedirectStandardError = true;
adbshell.EnableRaisingEvents = true;
adbshell.StartInfo.CreateNoWindow = true;
//adb.ErrorDataReceived += new DataReceivedEventHandler(adb_ErrorDataReceived);
adbshell.OutputDataReceived += new DataReceivedEventHandler(adbshell_OutputDataReceived);
try { var started = adbshell.Start(); }
catch (Exception ex)
{
Console.WriteLine(ex.Message + Environment.NewLine + ex.StackTrace);
}
//adb.BeginErrorReadLine();
adbshell.BeginOutputReadLine();
}
void adbshell_OutputDataReceived(object sender, DataReceivedEventArgs e)
{
output += (e.Data) + Environment.NewLine;
}
public void press_touch(string x, string y)
{
adbshell.StandardInput.WriteLine("input tap " + String.Format("{0} {1}", x, y));
Debug.WriteLine("pressed");
}
}
My Form class looks like
public partial class Form1 : Form
{
private bool _record;
private bool _selecting;
private Rectangle _selection;
//---------------------------------------------------------------------
public Form1()
{
InitializeComponent();
}
//---------------------------------------------------------------------
private void Form1_Load(object sender, System.EventArgs e)
{
ADBShell adbshell = new ADBShell();
adbshell.Start_ADBShell();
}
Everytime I have to make a new object in my methods, but i dont want to create everytime a new object. I would like make one time the object and access everytime to the same object. I do not want to make servel processes. I need only proccess and send and receive everytime the data to this process.
Do I have to make a static class?
How I can dispose and close my process after I'm quit my Form Class?

1: You do not want a static class. You want a SINGLETON - that is a class that has only one instance. This is normally accessed using a static property. At the easiest way this works like this:
public class A () {
private A () {}
public static A Instance {get; } = new A();
}
Access is via:
A.Instance
2: You do not. Processes do not get disposed. You exit the last thread that is not a background thread then the process ends. Otherwise you kill it, if that has to be done "In force" from the outside.

Move the ADBShell intialization in constructor of Form class. So this object will live till Form is not exited and to release resources by process make sure you call Process.close() in ADBShell class (Either in destructor or implement a IDisposable)
public partial class Form1 : Form
{
private bool _record;
private bool _selecting;
ADBShell adbshell;
private Rectangle _selection;
//---------------------------------------------------------------------
public Form1()
{
InitializeComponent();
adbshell = new ADBShell();
}
//---------------------------------------------------------------------
private void Form1_Load(object sender, System.EventArgs e)
{
adbshell.Start_ADBShell();
}
Dipose Process like this by adding Destructor
~ADBShell()
{
process.Close();
}
or implement Dispose method of IDisposable
Class ABDShell : IDisposable
{
...
...
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (disposing)
{
process.Close();
}
}
}
Updated singleton class
sealed class ADBShell
{
public static string output = String.Empty;
private ABDShell _instance;
private Process _processInstance;
// Note: constructor is 'private'
private ADBShell()
{
}
public Process ProcessInstance
{
if(_processInstance==null)
_processInstance = new Process();
get _processInstance ;
}
public static ADBShell Instance
{
get
{
if (_instance == null)
{
_instance = new ABDShell();
}
return _instance;
}
}
}
Now from your Form just do this
Process process = ABDShell.Instance.ProcessInstance;

// Sealed class makes sure it is not inherited. If inheritance required, go to Abstract Pattern.
class ADBShell
{
//public static property used to expose Singleton instance.
public static ADBShell Instance;
// private constructor
private ADBShell() { }
public static ADBShell getInstance()
{
if (Instance == null)
{
Instance = new Process;
}
}
}
Update
Thank you with your helps I solved my problems and now the ADB runs much faster instead of start everytime a new process.
public class ADBShell
{
private static ADBShell instance;
//private List<Employee> employeeList = null;
private Process shell = null;
private StreamWriter myWriter = null;
private static readonly object syncRoot = new object();
private ADBShell()
{
if (shell == null)
{
shell = new Process();
shell.StartInfo.FileName = (#"D:\ADB\ADB.exe");
shell.StartInfo.Arguments = "shell";
shell.StartInfo.RedirectStandardInput = true;
shell.StartInfo.UseShellExecute = false;
shell.StartInfo.WindowStyle = ProcessWindowStyle.Hidden;
shell.StartInfo.RedirectStandardOutput = true;
shell.StartInfo.CreateNoWindow = true;
shell.EnableRaisingEvents = true;
shell.OutputDataReceived += (sender, a) => Console.WriteLine(a.Data);
shell.Start();
myWriter = shell.StandardInput;
shell.BeginOutputReadLine();
}
}
public static ADBShell Instance()
{
if (instance == null)
{
lock (syncRoot)
{
if (instance == null)
{
instance = new ADBShell();
}
}
}
return instance;
}
public void tap(int x, int y)
{
myWriter.WriteLine("input tap {0} {1}", x.ToString(), y.ToString());
Thread.Sleep(10);
}
public void tap(string x, string y)
{
myWriter.WriteLine("input tap {0} {1}", x, y);
Thread.Sleep(10);
}
public void exit()
{
myWriter.WriteLine("exit");
}
public void Close()
{
myWriter.WriteLine("exit");
shell.WaitForExit();
if (!shell.HasExited)
{
shell.Kill();
}
shell.Close();
shell.Dispose();
myWriter.Close();
myWriter.Dispose();
}
}

Implement Unit of Work with multiple databases

I'm trying to implement Unit of Work and Generic Repository by following this great article. Only difference is that I have multiple databases context in my app. I came up with the below implementation but it seems awkward to say the least. What's the best way to do it ?
public class UnitOfWork : IDisposable
{
private MainDBDataContext MainDBDataContext = new MainDBDataContext();
private ReferenceDBDataContext ReferenceDBDataContext = new ReferenceDBDataContext();
private ProjectDBDataContext projectDBDataContext = new ProjectDBDataContext();
private VehicleRepository vehicleRepository;
private AccountRepository accountRepository;
public VehicleRepository VehicleRepository
{
get
{
if (this.vehicleRepository == null)
{
this.vehicleRepository = new VehicleRepository(projectDBDataContext,ReferenceDBDataContext);
}
return vehicleRepository;
}
}
public AccountRepository AccountRepository
{
get {
if (this.accountRepository == null)
{
this.accountRepository = new AccountRepository(projectDBDataContext);
}
return accountRepository;
}
}
public void Save()
{
projectDBDataContext.SubmitChanges();
ReferenceDBDataContext.SubmitChanges();
MainDBDataContext.SubmitChanges();
}
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
projectDBDataContext.Dispose();
MainDBDataContext.Dispose();
ReferenceDBDataContext.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
}

Implementation of processing items asynchronously

Is there any good implementation of processing queue items asynchronously?

If you're using .NET 4, a lot of this comes for free out of the box.
If you've already got all the items, you can use Parallel.ForEach. If you need a producer/consumer queue, you can use BlockingCollection<T> to wrap one of the concurrent collections (such as ConcurrentQueue<T> or ConcurrentStack<T>). How you use that is up to you; there's a blog post here going into a detailed example, and there are probably other similar posts around too. (You might want to look at the Parallel Team Blog for a lot more material.)

You could take a look at a Producer/Consumer pattern if you are unfortunate enough not to be using .net 4.
Here is my code I have disassembled, my apologies for the mess but you should be able to use this by adding to a project and recompiling, then creating your process using the resulting dll.
Enum for ChannelState:
public enum ChannelState
{
WaitingForSend,
WaitingForReceive,
Open
}
Interfaces:
public interface IChannel<TMessage>
{
// Methods
TMessage Receive();
void Send(TMessage message);
// Properties
bool CanReceive { get; }
bool CanSend { get; }
ChannelState State { get; }
}
using System;
public interface IReceiver<TMessage>
{
// Events
event EventHandler<MessageReceivedEventArgs<TMessage>> MessageReceived;
// Methods
void Activate();
void Deactivate();
// Properties
bool IsActive { get; }
}
Concrete classes:
using System.Collections.Generic;
using System.Threading;
using System;
public class BufferedChannel<TMessage> : IChannel<TMessage>
{
// Fields
private int _blockedReceivers;
private int _blockedSenders;
private Queue<TMessage> _buffer;
private int _capacity;
private EventWaitHandle _capacityAvailableEvent;
private EventWaitHandle _messagesAvailableEvent;
// Methods
public BufferedChannel()
{
this._buffer = new Queue<TMessage>();
this._messagesAvailableEvent = new EventWaitHandle(false, EventResetMode.AutoReset);
this._capacityAvailableEvent = new EventWaitHandle(true, EventResetMode.AutoReset);
this._capacity = 50;
}
public BufferedChannel(int bufferSize)
{
this._buffer = new Queue<TMessage>();
this._messagesAvailableEvent = new EventWaitHandle(false, EventResetMode.AutoReset);
this._capacityAvailableEvent = new EventWaitHandle(true, EventResetMode.AutoReset);
this._capacity = 50;
if (bufferSize <= 0)
{
throw new ArgumentOutOfRangeException("bufferSize", bufferSize, ExceptionMessages.ChannelsBufferSizeMustBeGreaterThanZero);
}
this._capacity = bufferSize;
}
public TMessage Receive()
{
Interlocked.Increment(ref this._blockedReceivers);
try
{
this._messagesAvailableEvent.WaitOne();
}
catch
{
lock (this._buffer)
{
Interlocked.Decrement(ref this._blockedReceivers);
}
throw;
}
lock (this._buffer)
{
Interlocked.Decrement(ref this._blockedReceivers);
this._capacityAvailableEvent.Set();
if ((this._buffer.Count - 1) > this._blockedReceivers)
{
this._messagesAvailableEvent.Set();
}
return this._buffer.Dequeue();
}
}
public void Send(TMessage message)
{
Interlocked.Increment(ref this._blockedSenders);
try
{
this._capacityAvailableEvent.WaitOne();
}
catch
{
lock (this._buffer)
{
Interlocked.Decrement(ref this._blockedSenders);
}
throw;
}
lock (this._buffer)
{
Interlocked.Decrement(ref this._blockedSenders);
this._buffer.Enqueue(message);
if (this._buffer.Count < this.BufferSize)
{
this._capacityAvailableEvent.Set();
}
this._messagesAvailableEvent.Set();
}
}
// Properties
public int BufferCount
{
get
{
lock (this._buffer)
{
return this._buffer.Count;
}
}
}
public int BufferSize
{
get
{
lock (this._buffer)
{
return this._capacity;
}
}
set
{
lock (this._buffer)
{
if (value <= 0)
{
throw new ArgumentOutOfRangeException("BufferSize", value, ExceptionMessages.ChannelsBufferSizeMustBeGreaterThanZero);
}
this._capacity = value;
if ((this._blockedSenders > 0) && (this._capacity > this._buffer.Count))
{
this._capacityAvailableEvent.Set();
}
}
}
}
public bool CanReceive
{
get
{
return true;
}
}
public bool CanSend
{
get
{
return true;
}
}
public ChannelState State
{
get
{
if (this._blockedSenders > 0)
{
return ChannelState.WaitingForReceive;
}
if (this._blockedReceivers > 0)
{
return ChannelState.WaitingForSend;
}
return ChannelState.Open;
}
}
}
using System;
using System.Collections.Generic;
using System.Threading;
using System.ComponentModel;
using System.Runtime.CompilerServices;
public sealed class Receiver<TMessage> : Component, IReceiver<TMessage>
{
// Fields
private volatile bool _continue;
private object _controlLock;
private volatile bool _disposed;
private Thread _receiverThread;
private bool _receiving;
private object _receivingLock;
private object _threadLock;
[CompilerGenerated]
private IChannel<TMessage> channel;
// Events
public event EventHandler<MessageReceivedEventArgs<TMessage>> MessageReceived;
// Methods
public Receiver(IChannel<TMessage> channel)
{
this._controlLock = new object();
this._threadLock = new object();
this._receivingLock = new object();
if (channel == null)
{
throw new ArgumentNullException("channel");
}
this.Channel = channel;
}
public void Activate()
{
this.CheckDisposed();
lock (this._controlLock)
{
if (this._receiverThread != null)
{
throw new InvalidOperationException();
}
this._continue = true;
this._receiverThread = new Thread(new ThreadStart(this.RunAsync));
this._receiverThread.IsBackground = true;
this._receiverThread.Start();
}
}
private void CheckDisposed()
{
if (this._disposed)
{
throw new ObjectDisposedException(base.GetType().Name);
}
}
public void Deactivate()
{
lock (this._controlLock)
{
if (this._continue)
{
this._continue = false;
lock (this._threadLock)
{
if (this._receiverThread != null)
{
this.SafeInterrupt();
this._receiverThread.Join();
this._receiverThread = null;
}
}
}
}
}
protected override void Dispose(bool disposing)
{
base.Dispose(disposing);
if (disposing)
{
this.Deactivate();
this._disposed = true;
}
}
private void OnMessageReceived(TMessage message)
{
EventHandler<MessageReceivedEventArgs<TMessage>> messageReceived = this.MessageReceived;
if (messageReceived != null)
{
messageReceived(this, new MessageReceivedEventArgs<TMessage>(message));
}
}
private void RunAsync()
{
while (this._continue)
{
TMessage message = default(TMessage);
bool flag = false;
try
{
lock (this._receivingLock)
{
this._receiving = true;
}
message = this.Channel.Receive();
flag = true;
lock (this._receivingLock)
{
this._receiving = false;
}
Thread.Sleep(0);
}
catch (ThreadInterruptedException)
{
}
if (!this._continue)
{
if (flag)
{
this.Channel.Send(message);
return;
}
break;
}
this.OnMessageReceived(message);
}
}
private void SafeInterrupt()
{
lock (this._receivingLock)
{
lock (this._threadLock)
{
if (this._receiving && (this._receiverThread != null))
{
this._receiverThread.Interrupt();
}
}
}
}
// Properties
protected override bool CanRaiseEvents
{
get
{
return true;
}
}
public IChannel<TMessage> Channel
{
[CompilerGenerated]
get
{
return this.channel;
}
[CompilerGenerated]
private set
{
this.channel = value;
}
}
public bool IsActive
{
get
{
lock (this._controlLock)
{
return (this._receiverThread != null);
}
}
}
}
using System;
using System.Runtime.CompilerServices;
public class MessageReceivedEventArgs<TMessage> : EventArgs
{
// Fields
[CompilerGenerated]
private TMessage message;
// Methods
public MessageReceivedEventArgs(TMessage message)
{
this.Message = message;
}
// Properties
public TMessage Message
{
[CompilerGenerated]
get
{
return this.message;
}
[CompilerGenerated]
private set
{
this.message = value;
}
}
}
using System.Threading;
public class BlockingChannel<TMessage> : IChannel<TMessage>
{
// Fields
private TMessage _message;
private EventWaitHandle _messageReceiveEvent;
private EventWaitHandle _messageReceiveyEvent;
private object _sendLock;
private ChannelState _state;
private object _stateLock;
// Methods
public BlockingChannel()
{
this._state = ChannelState.Open;
this._stateLock = new object();
this._messageReceiveyEvent = new EventWaitHandle(false, EventResetMode.AutoReset);
this._messageReceiveEvent = new EventWaitHandle(false, EventResetMode.AutoReset);
this._sendLock = new object();
}
public TMessage Receive()
{
this.State = ChannelState.WaitingForSend;
this._messageReceiveyEvent.WaitOne();
this._messageReceiveEvent.Set();
this.State = ChannelState.Open;
return this._message;
}
public void Send(TMessage message)
{
lock (this._sendLock)
{
this._message = message;
this.State = ChannelState.WaitingForReceive;
this._messageReceiveyEvent.Set();
this._messageReceiveEvent.WaitOne();
}
}
// Properties
public bool CanReceive
{
get
{
return true;
}
}
public bool CanSend
{
get
{
return true;
}
}
public ChannelState State
{
get
{
lock (this._stateLock)
{
return this._state;
}
}
private set
{
lock (this._stateLock)
{
this._state = value;
}
}
}
}

Pretty old but this is the good one that I know off http://www.codeproject.com/KB/cs/inprocessasynservicesincs.aspx

Use .NET 4 tasks.
var t = Task<int>.Factory.StartNew(() => ProcessItem());
Use the ConcurrencyOptions to set the maximum degree of parallelism on that processing.
If you want to roll it yourself, use BlockingCollection<T> which provides blocking and bounding capabilities for thread-safe collections and implement a separate thread (or threads) for the consumer.