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using System;
using System.Collections.Generic;
using System.Windows;
using System.Windows.Threading;
using Pfz.Collections;
namespace Pfz.Extensions
{
/// <summary>
/// Adds the SetValueAsyncAndOnce method to DependencyObjects.
/// </summary>
public static class PfzDependencyObjectExtensions
{
private sealed class InternalAutoTrimDictionary:
AutoTrimDictionary<KeyValuePair<DependencyObject, DependencyProperty>, object>
{
internal new object DisposeLock
{
get
{
return base.DisposeLock;
}
}
}
private static readonly InternalAutoTrimDictionary _valuesToSet = new InternalAutoTrimDictionary();
/// <summary>
/// Calls Dispatcher.BeginIncoke to set a value to a property.
/// If many calls are done before the begin invoke is executed, only the last Set remains, all others
/// will simple be ignored, effectivelly doing only one set.
/// </summary>
public static void SetValueAsyncAndOnce(this DependencyObject dependencyObject, DependencyProperty dependencyProperty, object value, DispatcherPriority priority = DispatcherPriority.Normal)
{
if (dependencyObject == null)
throw new ArgumentNullException("dependencyObject");
if (dependencyProperty == null)
throw new ArgumentNullException("dependencyProperty");
var propertyType = dependencyProperty.PropertyType;
if (value == null)
{
if (propertyType.IsValueType)
throw new ArgumentException("You are trying to set null to a " + dependencyProperty.Name + " which is a value-type property.");
}
else
{
Type valueType = value.GetType();
if (!propertyType.IsAssignableFrom(valueType))
throw new ArgumentException("value of type " + valueType.FullName + " can't be assigned to " + dependencyProperty.Name + ", which is of type " + propertyType.FullName + ".");
}
var pair = new KeyValuePair<DependencyObject, DependencyProperty>(dependencyObject, dependencyProperty);
lock(_valuesToSet.DisposeLock)
{
var valuesToSet = _valuesToSet;
if (valuesToSet.ContainsKey(pair))
valuesToSet[pair] = value;
else
{
valuesToSet.Add(pair, value);
dependencyObject.Dispatcher.BeginInvoke
(
new Action<KeyValuePair<DependencyObject, DependencyProperty>>(_SetValueAsync),
priority,
pair
);
}
}
}
private static void _SetValueAsync(KeyValuePair<DependencyObject, DependencyProperty> pair)
{
var dependencyObject = pair.Key;
var dependencyProperty = pair.Value;
object value;
lock(_valuesToSet.DisposeLock)
{
var valuesToSet = _valuesToSet;
value = valuesToSet[pair];
valuesToSet.Remove(pair);
}
dependencyObject.SetValue(dependencyProperty, value);
}
}
}
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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).