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DependencyPropertyHelper Class

Definition

Provides a single helper method (GetValueSource(DependencyObject, DependencyProperty)) that reports the property system source for the effective value of a dependency property.

public ref class DependencyPropertyHelper abstract sealed
public static class DependencyPropertyHelper
type DependencyPropertyHelper = class
Public Class DependencyPropertyHelper
Inheritance
DependencyPropertyHelper

Remarks

TheWPF property system is fairly complex, and relies on rationalizing the values that potentially come from a variety of inputs, based on an established value determination precedence. Because these sources potentially come from run-time code, from compiled markup, or even from run-time user settings, it can be useful to know exactly which participant in the dependency property value system established the value you obtain when calling GetValue at run-time on that property. If the value came from a different source than you had intended, you might need to adjust some aspect of your application. The value source might be a style, a theme, a local value, an animation, a binding, or a run-time based value such as system settings through themes or system resources. For more information, see Dependency Property Value Precedence.

Another mechanism that reports on the property in general, rather than a specific instance of the property on an object, is the property metadata. The property metadata is findable by calling GetMetadata and examining the returned PropertyMetadata (or one of several possible derived classes that the returned property metadata is castable to).

Methods

GetValueSource(DependencyObject, DependencyProperty)

Returns a structure that reports various metadata and property system characteristics of a specified dependency property on a particular DependencyObject.

IsTemplatedValueDynamic(DependencyObject, DependencyProperty)

Indicates whether a specified element belongs to an instance of a template that defines a value for the specified property that may change at runtime based on changes elsewhere.

Applies to