How do I unset a value from C# using the IStyle interface?

Most style elements have a distinct meaning when they are unset. Once I set a value with IStyle, I don’t know how to undo the change and go back to the unset state. Here’s an example: with visibility there are three possible settings (as currently observed, not sure what is intended):

  1. Visible : always visible even if parent is hidden
  2. Hidden : always hidden even when parent is visible.
    3 Unset : this means take your visibility from your parent

Once I have changed the visibility of an element to “Hidden” I don’t know how to get back to the unset state where the element takes its visibility from its parent. Any thoughts?

Would this help?

Thanks, that’s exactly the kind of thing I am looking for and there are definitely places I’ll use it, but it doesn’t work for visibility.
The corresponding enum declarations:

public enum Visibility
{
Visible = 0,
Hidden = 1
}

public enum StyleKeyword
{
Undefined = 0,
Null = 1,
Auto = 2,
None = 3,
Initial = 4
}

So if I try to cast a StyleKeyword.Null to Visibility I’ll just get Hidden. Perhaps Visibility needs a Null value.