Shape.AddToContainers Method (Visio)
Adds the shape to all underlying containers that allow it as a member.
expression A variable that represents a Shape object.
When you call the AddToContainers method, Microsoft Visio uses the setting of the ContainerProperties.ResizeAsNeeded property for each container to determine how the container resizes.
If the underlying container is a list, the shape is added as a normal container member, and not as a list member.
The AddToContainers method works only if the shape sits at least partially on top of a container that does not already contain it.