How to catch exception on a page while running automated tests

I am doing automation testing of a web application using selenium. While running automation testing of web application you encounter application errors. Is there any way to detect those exceptions. Specially exceptions that are on the page which causes the page to hang up as it is not finding the element it is looking for or page stays on the same page and waitforpage() fun开发者_JS百科ction keeps running. How can I solve it. Please help

You'll need to put in screen-scraping code, where you search the page for various messages.