How can I highlight/outline a Visual object in WPF?

Question

If I had a Canvas with n number of Visual objects of any shape or size, how would I highlight/outline a Visual object programmatically?

Is there something built into WPF to help me?

Answer 1

Having read the comments in the other answer -- in which you state that you wish the outline to conform to the shape of the visual -- I can only suggest you take a look at the BitmapEffects. There is one for an Outer Glow effect.

Duplicating the visuals themselves would probably be less efficient, and would probably produce a great number of complications due to other aspects of those items, such as any bindings.

Edit: In .NET 4.0, BitmapEffects property and the BitmapEffect class are obsolete. You'll get an exception thrown. Instead, you now have the System.Windows.Media.Effects.Effect class and its derived classes, along with properties such as Visual.VisualEffect.