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using System.Collections;
using System.Collections.Generic;
using System.Threading;
using Pfz.Threading;
namespace Pfz.Collections
{
/// <summary>
/// This enumerator returns a "next value" every time the actual value is set, but
/// if many sets are done before the client is able to process them, the
/// intermediate values are lost, so only the "actual" one is got.
/// </summary>
/// <typeparam name="T">The type of the values.</typeparam>
public class ActualValueEnumerator<T>:
ThreadSafeDisposable,
IFastEnumerator<T>
where
T: class
{
private ManualResetEvent fManualResetEvent = new ManualResetEvent(false);
#region Dispose
/// <summary>
/// Only sets the event so any waiting thread is free.
/// </summary>
protected override void Dispose(bool disposing)
{
if (disposing)
{
fActualValue = null;
var manualResetEvent = fManualResetEvent;
if (manualResetEvent != null)
manualResetEvent.Set();
}
base.Dispose(disposing);
}
#endregion
#region Property ActualValue
private T fActualValue;
/// <summary>
/// Gets or sets the actual value.
/// </summary>
public T ActualValue
{
get
{
T result = null;
AbortSafe.UnabortableLock
(
DisposeLock,
() =>
{
if (!WasDisposed)
result = fActualValue;
}
);
return result;
}
set
{
AbortSafe.UnabortableLock
(
DisposeLock,
() =>
{
CheckUndisposed();
fActualValue = value;
fManualResetEvent.Set();
}
);
}
}
#endregion
#region Methods
#region GetNext
/// <summary>
/// Gets the next value.
/// </summary>
public T GetNext()
{
if (WasDisposed)
return null;
fManualResetEvent.WaitOne();
T result = null;
AbortSafe.UnabortableLock
(
DisposeLock,
() =>
{
if (!WasDisposed)
{
result = fActualValue;
fManualResetEvent.Reset();
}
}
);
return result;
}
#endregion
#region p_GetEnumerator
private IEnumerator<T> p_GetEnumerator()
{
while(true)
{
var value = GetNext();
if (value == null)
yield break;
yield return value;
}
}
#endregion
#endregion
#region IFastEnumerator Members
object IFastEnumerator.GetNext()
{
return GetNext();
}
#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).