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using System;
using System.Collections;
using System.Collections.Generic;
using System.Threading;
namespace Pfz.Collections
{
/// <summary>
/// Class that enumerates an ActualValueCollection.
/// If three new values appears and you call GetNext only once, you
/// will only receive the last value. If you call GetNext when there is no
/// value, your thread will be blocked waiting for a new value.
/// </summary>
public sealed class ActualValueEnumerator<T>:
IFastEnumerator<T>,
IEnumerator<T>
where
T: class
{
private readonly ActualValueCollection<T> _collection;
private T _lastValue;
internal ActualValueEnumerator(ActualValueCollection<T> collection)
{
_collection = collection;
}
#region IDisposable
// do nothing. The dispose should be called only by the thread
// who created this, so it is not needed to free a thread.
void IDisposable.Dispose()
{
}
bool IAdvancedDisposable.WasDisposed
{
get
{
return false;
}
}
#endregion
/// <summary>
/// Gets the next value in the collection. A return of null means
/// the collection ended.
/// </summary>
public T GetNext()
{
lock(_collection._lock)
{
while(true)
{
if (_collection.WasDisposed)
{
_lastValue = null;
return null;
}
var value = _collection.Value;
if (value != _lastValue)
{
_lastValue = value;
return value;
}
Monitor.Wait(_collection._lock);
}
}
}
/// <summary>
/// Gets the last read value.
/// </summary>
public T Current
{
get
{
return _lastValue;
}
}
/// <summary>
/// Tries to get a new value and store it in the Current property.
/// </summary>
public bool MoveNext()
{
return GetNext() != null;
}
#region IEnumerator Membres
object IEnumerator.Current
{
get
{
return _lastValue;
}
}
void IEnumerator.Reset()
{
throw new NotSupportedException();
}
#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).