'System.Windows.Documents.Run' is not a Visual or Visual3D' Exception

[punker76]

Original author: manfred....@gmail.com (June 04, 2010 12:57:40)

Suddenly an unhandled Exception is thrown namely:
'System.Windows.Documents.Run' is not a Visual or Visual3D'

The exception occurs in
VisualTreeExtensions.cs in the Method GetVisualAncestor<T>(this
DependencyObject d) where T : class

To solve the problem I would add a check like so:
public static T GetVisualAncestor<T>(this DependencyObject d) where T :
class
{
if (d is Visual || d is System.Windows.Media.Media3D.Visual3D)
{
DependencyObject item = VisualTreeHelper.GetParent(d);

    while (item != null)
    {
        T itemAsT = item as T;
        if (itemAsT != null) return itemAsT;
        item = VisualTreeHelper.GetParent(item);
    }
}

return null;

}

Original issue: http://code.google.com/p/gong-wpf-dragdrop/issues/detail?id=17

[punker76]

From gro...@gmail.com on June 22, 2010 10:35:56
Could you give me more information about this issue please? Where is the Run defined? If you could provide a minimal XAML example that would be helpful.

[punker76]

From jbo...@gmail.com on February 14, 2011 17:16:39
I was having this problem too. But using a fix like this prevented me from dragging something that has a Run in it if the user clicks on the Run.
Here is a patch to fix it. The patch also updates to VS 2010 and dot net 4, but you can reverse the changes to the .csproj file if you don't want that.