check all checkbox in a webpage automatically!

Question

hi

i have an web page that has 200 checkbox in it
and i must check all checkbox in this page and else similar page

how can i write a program that can do it automatically?

i think i can get place of checkboxs in pixel and i put cursor of mouse on that and automatically click there

but it not seems be true way

is there any way?

or better way?

thanks