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+---
+title: "How to: Implement a Dependency Property"
+description: Define a dependency property in Windows Presentation Foundation, by backing a common language runtime property with a DependencyProperty field.
+ms.date: "03/30/2017"
+dev_langs: 
+  - "csharp"
+  - "vb"
+helpviewer_keywords: 
+  - "dependency properties [WPF], backing properties with"
+  - "properties [WPF], backing with dependency properties"
+ms.assetid: 855fd6d7-19ac-493c-bf5e-2f40b57cdc92
+---
+# How to: Implement a Dependency Property
+This example shows how to back a common language runtime (CLR) property with a <xref:System.Windows.DependencyProperty> field, thus defining a dependency property. When you define your own properties and want them to support many aspects of [!INCLUDE[TLA#tla_winclient](../../../includes/tlasharptla-winclient-md.md)] functionality, including styles, data binding, inheritance, animation, and default values, you should implement them as a dependency property.  
+  
+## Example  
+ The following example first registers a dependency property by calling the <xref:System.Windows.DependencyProperty.Register%2A> method. The name of the identifier field that you use to store the name and characteristics of the dependency property must be the <xref:System.Windows.DependencyProperty.Name%2A> you chose for the dependency property as part of the <xref:System.Windows.DependencyProperty.Register%2A> call, appended by the literal string `Property`. For instance, if you register a dependency property with a <xref:System.Windows.DependencyProperty.Name%2A> of `Location`, then the identifier field that you define for the dependency property must be named `LocationProperty`.  
+  
+ In this example, the name of the dependency property and its CLR accessor is `State`; the identifier field is `StateProperty`; the type of the property is <xref:System.Boolean>; and the type that registers the dependency property is `MyStateControl`.  
+  
+ If you fail to follow this naming pattern, designers might not report your property correctly, and certain aspects of property system style application might not behave as expected.  
+  
+ You can also specify default metadata for a dependency property. This example registers the default value of the `State` dependency property to be `false`.  
+  
+ [!code-csharp[PropertySystemEsoterics#MyStateControl](~/samples/snippets/csharp/VS_Snippets_Wpf/PropertySystemEsoterics/CSharp/SDKSampleLibrary/class1.cs#mystatecontrol)]
+ [!code-vb[PropertySystemEsoterics#MyStateControl](~/samples/snippets/visualbasic/VS_Snippets_Wpf/PropertySystemEsoterics/visualbasic/sdksamplelibrary/class1.vb#mystatecontrol)]  
+  
+ For more information about how and why to implement a dependency property, as opposed to just backing a CLR property with a private field, see [Dependency Properties Overview](dependency-properties-overview.md).  
+  
+## See also
+
+- [Dependency Properties Overview](dependency-properties-overview.md)
+- [How-to Topics](properties-how-to-topics.md)