Use the Permission interface DirShowInList property to determine if a group or client can see a folder, and to display or hide the folder.
HRESULT DirShowInList([out, retval] VARIANT_BOOL *pVal);
HRESULT DirShowInList([in] VARIANT_BOOL newVal);
True = Displayed
False = Hidden
Refer to "Difference between DirList and DirShowInList Permission" in Granting Permission to View a List of Folder Contents (DirList) to view and example of the two permissions and how they differ.
Refer to Permission Interface Properties for an illustration of how this and other Permission properties can be accessed in the Administrator interface.