Question

I used this “guide”,
but the difference is that I don’t want to restrict the object Im attaching the property on, to UIElement
I’d like to attach a property to the most generic item : object, so here is my code :

    public static readonly DependencyProperty QbNameProperty =    DependencyProperty.RegisterAttached(
        "QbName",
        typeof(string),
        typeof(QbName),
        new PropertyMetadata("")
    );

    public static void SetQbName(object obj, string name)
    {
        obj.SetValue(QbNameProperty, name);
    }
    public static Boolean GetQbName(object obj)
    {
        return (Boolean)obj.GetValue(QbNameProperty);

The thing is that SetValue and GetValue do not exist for object… I tried to look everywhere (SO and google) and didnt find any solution but as far as I understood the article I linked, attachedProperties are not restricted to UIElements right ?
So… what should I do ?

ps : to complete my answer I HAVE TO get a Name for some objects Im parsing from a DLL (and display it in a TreeView) so, if I don’t have a Name fields/property, I’ll add the attachment !

Answer 1

You can’t attach properties to Object (or you’ll be able to extend the whole framework..).
Dependency properties can only be used by objects inheriting from DependencyObject.

/// <summary>
/// QbName
/// </summary>
public class QbName : DependencyObject
{
    /// <summary>
    /// 
    /// </summary>
    public static readonly DependencyProperty NameProperty = DependencyProperty.RegisterAttached(
        "Name",
        typeof(string),
        typeof(QbName),
        new PropertyMetadata("")
        );

    /// <summary>
    /// Sets the name.
    /// </summary>
    /// <param name="element">The element.</param>
    /// <param name="value">The value.</param>
    public static void SetName(DependencyObject element, string value)
    {
        element.SetValue(NameProperty, value);
    }

    /// <summary>
    /// Gets the name.
    /// </summary>
    /// <param name="element">The element.</param>
    /// <returns></returns>
    public static string GetName(DependencyObject element)
    {
        return element.GetValue(NameProperty).ToString();
    }
}

Then you can use the static methods:

QbName qb = new QbName();
QbName.SetName(qb, "test");