getNumLayers

Get the number of layers.
getNumLayers([out, retval] int *numLayers)
This function returns the number of layers in the PDF file.

Layers are numbered 0 through n-1 (where n is the value returned by getNumLayers). Note that many PDF files have zero layers, meaning that there is no content that can be selectively turned on or off. (This is different from some other formats which always have at least one layer.)

VB6:
n = viewer.getNumLayers For i = 0 To n-1 layer = viewer.getLayer(i) name = viewer.getLayerName(layer) visible = viewer.getLayerVisibility(layer) ' ... add a list entry using name and visible ... Next i
getLayer
getLayerName
getLayerVisibility
setLayerVisibility
getLayerViewState
getLayerPrintState