--- title: "How to: Implement Property Change Notification" description: Enable your properties to automatically notify a binding source when the property value changes in Windows Presentation Foundation (WPF). ms.date: "03/30/2017" dev_langs: - "csharp" - "vb" helpviewer_keywords: - "notifications of change [WPF]" - "data binding [WPF], property change notifications" - "change notifications [WPF]" - "properties [WPF], change notifications" ms.assetid: 30b59d9e-8c3a-4349-aa82-4be837e841cf --- # How to: Implement Property Change Notification To support or binding to enable your binding target properties to automatically reflect the dynamic changes of the binding source (for example, to have the preview pane updated automatically when the user edits a form), your class needs to provide the proper property changed notifications. This example shows how to create a class that implements . ## Example To implement you need to declare the event and create the `OnPropertyChanged` method. Then for each property you want change notifications for, you call `OnPropertyChanged` whenever the property is updated. [!code-csharp[SimpleBinding#PersonClass](~/samples/snippets/csharp/VS_Snippets_Wpf/SimpleBinding/CSharp/Person.cs#personclass)] [!code-vb[SimpleBinding#PersonClass](~/samples/snippets/visualbasic/VS_Snippets_Wpf/SimpleBinding/VisualBasic/Person.vb#personclass)] To see an example of how the `Person` class can be used to support binding, see [Control When the TextBox Text Updates the Source](how-to-control-when-the-textbox-text-updates-the-source.md). ## See also - [Binding Sources Overview](binding-sources-overview.md) - [Data Binding Overview](/dotnet/desktop-wpf/data/data-binding-overview) - [How-to Topics](data-binding-how-to-topics.md)