>Hi,
>How to implement this:

private void SetAttachedProperty(FrameworkElement fe, string propertyName, object value)
>        {
>        }

when called, for example, with:

SetAttachedProperty(new TextBlock(), "Canvas.Left", 50);

>>>>>>

I was watching this one to see if any one had an answer. So far no joy :-(

Have you considered using XamlReader/Writer for this instead of rolling your own property setter?