using System.Windows; namespace ModernWpfPlayground { public partial class ContentDialogExample { public static readonly DependencyProperty MessageProperty = DependencyProperty.Register( "Message", typeof(string), typeof(ContentDialogExample), new PropertyMetadata(default(string))); public string Message { get => (string) GetValue(MessageProperty); set => SetValue(MessageProperty, value); } public ContentDialogExample() { InitializeComponent(); } } }