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using System;
using Pfz.Threading;
namespace Pfz.Collections
{
/// <summary>
/// This class connects to a EnumeratorDistributor and is able
/// to use GetNext to get a next frame when one is available, while it is
/// also able to "loose" values if the real enumerator is running faster
/// than this client. This is useful when getting frames from a web-cam,
/// for example.
/// </summary>
public class EnumeratorDistributorClient<T>:
ThreadSafeDisposable,
IFastEnumerator<T>
where
T: class
{
internal PooledAutoResetEvent _autoResetEvent = new PooledAutoResetEvent(false);
#region Constructor
/// <summary>
/// Creates a new multi-client enumerator connected to the given distributor.
/// </summary>
public EnumeratorDistributorClient(EnumeratorDistributor<T> distributor)
{
if (distributor == null)
throw new ArgumentNullException("distributor");
Distributor = distributor;
lock(distributor.DisposeLock)
{
distributor.CheckUndisposed();
distributor._clientEnumerators.Add(this);
}
}
#endregion
#region Dispose
/// <summary>
/// Releases the resources used by this enumerator and removes it from
/// the distributor list.
/// </summary>
protected override void Dispose(bool disposing)
{
if (disposing)
{
var distributor = Distributor;
if (distributor != null)
{
Distributor = null;
lock(distributor.DisposeLock)
{
var clientEnumerators = distributor._clientEnumerators;
if (clientEnumerators != null)
clientEnumerators.Remove(this);
}
}
var autoResetEvent = _autoResetEvent;
if (autoResetEvent != null)
autoResetEvent.Set();
}
base.Dispose(disposing);
}
#endregion
#region Property - Distributor
/// <summary>
/// Gets the Distributor used by this enumerator.
/// </summary>
public EnumeratorDistributor<T> Distributor { get; private set; }
#endregion
#region Method - GetNext
/// <summary>
/// Gets the actual value of the distributor or waits until a new
/// value is available.
/// </summary>
public virtual T GetNext()
{
var autoResetEvent = _autoResetEvent;
if (autoResetEvent == null)
return null;
try
{
autoResetEvent.WaitOne();
var distributor = Distributor;
if (distributor == null)
return null;
lock(distributor.DisposeLock)
{
if (distributor.WasDisposed)
{
var disposeException = distributor.DisposeException;
if (disposeException != null)
throw new ObjectDisposedException("This enumerator was disposed by an exception in its distributor.", disposeException);
return null;
}
return distributor.ActualValue;
}
}
finally
{
var distributor = Distributor;
if (distributor == null || distributor.WasDisposed)
{
_autoResetEvent = null;
autoResetEvent.Dispose();
}
}
}
#endregion
}
}
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I started to program computers when I was 11 years old, as a hobbyist, programming in AMOS Basic and Blitz Basic for Amiga.
At 12 I had my first try with assembler, but it was too difficult at the time. Then, in the same year, I learned C and, after learning C, I was finally able to learn assembler (for Motorola 680x0).
Not sure, but probably between 12 and 13, I started to learn C++. I always programmed "in an object oriented way", but using function pointers instead of virtual methods.
At 15 I started to learn Pascal at school and to use Delphi. At 16 I started my first internship (using Delphi). At 18 I started to work professionally using C++ and since then I've developed my programming skills as a professional developer in C++ and C#, generally creating libraries that help other developers do their work easier, faster and with less errors.
Want more info or simply want to contact me?
Take a look at:
http://paulozemek.azurewebsites.net/
Or e-mail me at: paulozemek@outlook.com
Codeproject MVP 2012, 2015 & 2016
Microsoft MVP 2013-2014 (in October 2014 I started working at Microsoft, so I can't be a Microsoft MVP anymore).