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只操作顶层走线的表达式为:expr=IsTrack and OnTopLayer|mask=True|apply=True 0 J- ?+ w6 ?# i只操作底层走线的表达式为:expr=IsTrack and OnBottomLayer|mask=True|apply=True5 d' n- T" T; u6 m! U& R8 l
只操作电气走线的表达式为:expr=IsTrack and IsElectrical|mask=True|apply=True, A, p8 \- x0 R+ t8 r/ O- Y
只操作过孔的表达式为: expr=IsVia|mask=True|apply=True7 s0 V# c! b" ?) n3 \& z- ^* D
只操作顶层元件的表达式为:expr=IsComponent and OnTopLayer|mask=True|apply=True , r9 `* \/ |( `; n5 p- t1 F Y. G" w a: O$ z