This document is no longer available beyond version 4. Information can now be found here: OnLayer for version 5

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Parent page: PCB Query Functions - Membership Checks


Returns all objects whose Layer property complies with the Query.


OnLayer(Layer : String) : Boolean/Boolean_String

Layer is the name of the layer as it appears on the Layers & Colors tab of the View Configuration panel.

Example Usage

OnLayer('Top Layer')
OnLayer('Top Layer') = True
OnLayer('Top Layer') = 'True'

Returns all objects whose Layer property is Top Layer.

Not OnLayer('Mechanical 3')
OnLayer('Mechanical 3') = False
OnLayer('Mechanical 3') = 'False'

Returns all objects except objects whose Layer property is Mechanical 3 layer.


  1. The single quote characters (') at the start and end of Layer are mandatory.
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