atzimler

[TestFixture]
public class LetsCheckTheEventHandlers
{
    [Test]
    public void ChainedEventHandlers()
    {
        var m = new MultiplyByTwo();
        var s = new CreateResultStars(m);
        Assert.AreEqual(string.Empty, s.Stars);

atzimler

dpd.AddValueChanged(_multiplier, (o, e) => RecalculateStars());

atzimler

var dpd = DependencyPropertyDescriptor.FromProperty(MultiplyByTwo.ResultProperty, typeof(MultiplyByTwo));

atzimler

public class CreateResultStars
{
    private readonly MultiplyByTwo _multiplier;

    public string Stars { get; private set; }

    public CreateResultStars(MultiplyByTwo multiplier)
    {
        _multiplier = multiplier;

atzimler

public class MultiplyByTwo : DependencyObject
{
    private static readonly DependencyPropertyKey ResultPropertyKey =
        DependencyProperty.RegisterReadOnly(nameof(Result), typeof(int), typeof(MultiplyByTwo),
            new PropertyMetadata(0));

    public static readonly DependencyProperty NumberProperty =
        DependencyProperty.Register(nameof(Number), typeof(int), typeof(MultiplyByTwo),
            new PropertyMetadata(0, CalculateResult));

atzimler

public static readonly DependencyProperty NumberProperty =
  DependencyProperty.Register(nameof(Number),
                              typeof(int),
                              typeof(MultiplyByTwo),
                              new PropertyMetadata(0, CalculateResult));

atzimler

public static readonly DependencyProperty AProperty =
    DependencyProperty.Register(nameof(A),
                                typeof(int),
                                typeof(AddCalculation),
                                new PropertyMetadata(0, AddNumbers));
private static void AddNumbers(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
    var ac = (AddCalculation)d;
    ac.SetValue(ResultPropertyKey, ac.A + ac.B);
}

atzimler

[TestFixture]
public class ReadOnlyDependencyPropertiesShould
{
    [Test]
    public void BeReadableByAnyone()
    {
        var ac = new AddCalculation
        {
            A = 42
        };

atzimler

public int Result
{
    get { return (int)GetValue(ResultProperty); }
}

atzimler

public static readonly DependencyProperty ResultProperty =
    ResultPropertyKey.DependencyProperty;