ImportLayerState() reads the passed-in filename (saved by a previous export) and extracts layer states to import. If an import file layer state has the same name as a layer state already existing in the drawing, the imported layer state is ignored. If an import file layer state name is not found in the drawing, it is created in the drawing. If any newly-created layer states refer to layers which are nonexistent in the drawing, the layers are created using default settings. 

Public Function ImportLayerState(
    fileName As string
) As void

public void ImportLayerState(
    string fileName
);