I want to be able to turn on and off the layer (visibleLayers) by ComboBox. I'm attempting to create three ComboBoxs for the user to toggle the visibility of layers in a dynamic map service layer. these three ComboxBoxs Respectively represent "dynamic services", "Year", "Month" . I know the code is problem, but I will not modify,Please help me. I referred to the http://forums.arcgis.com/threads/2106-Radio-Button-on-off-Layers?highlight=Dynamic+layers