This　paper　studies　the　problem　of　designing　robust　H-infinity　controllers　for　networked　control　systems　(NCSs)　with　both　network-induced　time　delay　and　packet　dropout　by　using　active　varying　sampling　period　method,　where　the　sampling　period　switches　in　a　finite　set.　An　active　varying　sampling　period　method　using　both　clock-driven　and　event-driven　sensor　is　proposed,　then　by　modeling　the　system　with　varying　sampling　period　as　a　switched　system,　H-infinity　controllers　are　designed　by　using　LMI-based　method.　The　simulation　results　illustrate　the　effectiveness　of　the　active　varying　sampling　period　method　and　the　proposed　H-infinity　controller　design.