For ex. I have a task to chnage mouse pointer on mouse hover. The answer is too simple
use CSS.No, my css is not working due to some un avoidable reasons.
Finally I come to the conclusion i.e
Make a global.js contains
Then implement this function like
1) Put an HTML button of the page
2) Then on onmouseover event write code "onmouseover="set_mouse_pointer(this);"
3) View that page in browser.
You will see the effect.