javascript - location.href and fallback for page not available -

javascript - location.href and fallback for page not available -

is there way when reload page javascript have fallback if target page not available?

example:

i doing

location.href = 'http://www.google.com'

but maybe google downwards (or maybe url not exist anymore or malformed, etc...) , in case, avoid reloading. possible?

you can't recognize happens after visitor leaves page. thing. maybe check before redirect, if can connect (client side) javascript if website available , perform redirect. have check before redirect, not after fallback.

javascript