Gets or sets the scope limits for property value inheritance, resource key lookup, and RelativeSource FindAncestor lookup.
Assembly: PresentationFramework (in PresentationFramework.dll)
Certain boundaries in the element tree set to deliberately limit the scope of inheritance behavior, to a force resource lookup to check the application resources, or to prevent a RelativeSource FindAncestor lookup from querying the current element or any further. RelativeSource FindAncestor lookup occurs when a binding uses a RelativeSource that has its Mode property set to the RelativeSourceMode.FindAncestor value.
If you want your derived class to set this property, you should do so within the static constructor or in other initialization routines.