Setting a custom property within a WPF/Silverlight page

Question

This sounds like it should be simple. I have a Page declared in XAML in the normal way (i.e. with "Add new item...") and it has a custom property. I\'

Answer 1

You would need to make it an attachable property as Pavel noted, then you can write something like this

However, with only this code-behind, you will get this error instead:

The attachable property 'MyProperty' was not found in type 'SkeetPage'.

The attached property 'SkeetPage.MyProperty' is not defined on 'Page' or one of its base classes.

---

Edit

Unfortunately, you have to use Dependency Properties. Here's a working example

Page

Code-behind

using System.Windows;
using System.Windows.Controls;

namespace JonSkeetTest
{
    public partial class SkeetPage
    {
        public SkeetPage()
        {
            InitializeComponent();
        }

        public static readonly DependencyProperty MyPropertyProperty = DependencyProperty.Register(
          "MyProperty",
          typeof(string),
          typeof(Page),
          new FrameworkPropertyMetadata(null,
              FrameworkPropertyMetadataOptions.AffectsRender
          )
        );

        public static void SetMyProperty(UIElement element, string value)
        {
            element.SetValue(MyPropertyProperty, value);
        }
        public static string GetMyProperty(UIElement element)
        {
            return element.GetValue(MyPropertyProperty).ToString();
        }

        public string MyProperty
        {
            get { return GetValue(MyPropertyProperty).ToString(); }
            set { SetValue(MyPropertyProperty, value); }
        }

        private void ButtonTest_Pressed(object sender, RoutedEventArgs e)
        {
            MessageBox.Show(MyProperty);
        }
    }
}

If you press the button, you will see "Testing..." in a MessageBox.