How can connecte a plug to a light switch?

Lets be sure we all use the same terms. The PLUG is the 2 or 3 pronged thing at the end of a fixture cord. A light switch is the thing on the wall which you flip to turn on the power. Are you sure you need to connect these two?

You could use an outlet to plug the lamp into and then control the outlet with a wall switch.

Is that what you are thinking? Oh, by the way, you could also actually tell us what you are trying to accomplish.