How can i prevent cheating while online test?

Hello guys i want to share and get some thing. 

 

Can I Control windows explorer from client side of my web application

Actually my scenario is i want to create a anti cheat system for my web application and while user giving its test online i want to prevent it from cheating to open another browser instance to search

 

 

I just came up with an idea if i close windows explorer while user giving its test and after test i run explorer back to were it was before so i can prevent user for doing many things from its pc