Well.... if they're anything like the ones here in the U.S.,they don't actually have a "switch", but they are shipped with a little piece of cellophane or plastic under the positive end of the 3A storage battery that stores the solar energy until night. Additionally, these little batteries sometimes need twisting in their fittings to work.
If you place your hand over the solar panel on top,you'll notice the light comes onsince there's also a light sensor installed limiting the operation of the light to after a minimum light setting...