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Topic: The order of call Callback in DependencyProperty

Decided to check up the order of call Callback' for DependencyProperty a following code: public class CustomControl: UserControl {public static readonly DependencyProperty CustomPropertyProperty; public static event EventHandler PropertyChangedCallbackIsRised; public static event EventHandler CoerceValueCallbackIsRised; public static event EventHandler ValidateValueCallbackIsRised; static CustomControl () {var metadata = new FrameworkPropertyMetadata (10, CustomPropertyChangedValuCallback, CustomPropertyCoerceValueCallback); CustomPropertyProperty = DependencyProperty. Register ("MyProperty", typeof (int), typeof (CustomControl), metadata, CustomPropertyValidateValueCallback);} private static void CustomPropertyChangedValuCallback (DependencyObject d, DependencyPropertyChangedEventArgs e) {PropertyChangedCallbackIsRised?.Invoke (null, null);} private static object CustomPropertyCoerceValueCallback (DependencyObject d, object baseValue) {CoerceValueCallbackIsRised?.Invoke (null, null); return baseValue;} private static bool CustomPropertyValidateValueCallback (object value) {ValidateValueCallbackIsRised?.Invoke (null, null); return true;} public int CustomProperty {get {return (int) GetValue (CustomPropertyProperty);} set {SetValue (CustomPropertyProperty, value);}}} public partial class MainWindow: Window {public MainWindow () {InitializeComponent (); CustomControl.PropertyChangedCallbackIsRised + = CustomControl_PropertyChangedCallbackIsRised; CustomControl. CoerceValueCallbackIsRised + = CustomControl_CoerceValueCallbackIsRised; CustomControl.ValidateValueCallbackIsRised + = CustomControl_ValidateValueCallbackIsRised;//In XAML to a marking is TextBox txtInfo in which it is deduced  var customControl = new CustomControl (); txtInfo. Text = "Deafult value:" + customControl. CustomProperty + "\r\n"; customControl. CustomProperty = 100; txtInfo. Text + = "New value1:" + customControl. CustomProperty + "\r\n"; customControl. CustomProperty = 1000; txtInfo. Text + = "New value2:" + customControl. CustomProperty;} private void CustomControl_ValidateValueCallbackIsRised (object sender, EventArgs e) {txtInfo. Text + = "ValidateValueCallback\r\n";} private void CustomControl_CoerceValueCallbackIsRised (object sender, EventArgs e) {txtInfo. Text + = "CoerceValueCallback\r\n";} private void CustomControl_PropertyChangedCallbackIsRised (object sender, EventArgs e) {txtInfo. Text + = "PropertyChangedCallback\r\n";} } Received an output: Deafult value: 10 ValidateValueCallback CoerceValueCallback PropertyChangedCallback New value1: 100 ValidateValueCallback CoerceValueCallback PropertyChangedCallback New value2: 1000 Thus in the book "Pro WPF 4.5 in #" Matthew MacDonald' affirms that the order should be such: CoerceValueCallback ValidateValueCallback PropertyChangedCallback From here two questions: 1) Why between values 10 and 100 ValidateValueCallback takes off two times? 2) why between values 100 and 1000 order another?

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Re: The order of call Callback in DependencyProperty

Hello, Cynic, you wrote: the C> Received an output: a C> Deafult value: 10 Cs> ValidateValueCallback a C> CoerceValueCallback a C> PropertyChangedCallback a C> New value1: 100 Cs> ValidateValueCallback a C> CoerceValueCallback a C> PropertyChangedCallback a C> New value2: 1000 Cs> From here two questions: the C> 1) Why between values 10 and 100 ValidateValueCallback takes off two times? A C> 2) Why between values 100 and 1000 order another? On an output of the such you will not tell a C> Thus in the book "Pro WPF 4.5 in #" Matthew MacDonald' affirms that the order should be such: I do not know that in the book, but here it is logical enough. Validate is a validation of value for property, and Coerce - adjustment within the limits of admissible. Result Coerce can be reconsidered without assignment, therefore original value, to Coerce, should be .

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Re: The order of call Callback in DependencyProperty

Hello, MxMsk, you wrote: MM> On an output of the such you will not tell Ups, early  that new year started to mark MM> I do not know that in the book, but here it is logical enough. Validate is a validation of value for property, and Coerce - adjustment within the limits of admissible. Result Coerce can be reconsidered without assignment, therefore original value, to Coerce, should be . Probably the author  confused that.

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Re: The order of call Callback in DependencyProperty

Hello, Cynic, you wrote: Cs> Ups, early  started to mark new year that Well, then with the coming!