javascript/php redirect and already indexed pages in google

[scorpion]

My question is this: suppose I have a site that is already extensively indexed in google (subpages, etc..), if you slap on a php or javascript redirect on the main page and google cannot read this code, then would your pages continue to remain in google without any effect even though users would be redirected off the main page everytime?

What would be the implications of this? I mean the current pages will still be available, but nobody going to the main page would see it as it would redirect somewhere else...

[lazerzubb]

Yes your page would still be indexed, i am not sure about the PHP thing though. All i can say that i would probably advise against using it, people have the belife that Google can't read Javascript, and they can believe that, but 50+phd's doesn't have a problem finding javascript redirects, believe me.

Also if any of your competitors find it and reports it there might be a chance that you will be labeled with a PR 0 or something similar.
If the page/site has moved i would advise using a Server Redirect for this, and not a browser redirect.

[WebGuerrilla]

PHP would be a server side redirect, so Google would be aware of it. (unless of course you set it up to detect gbot and then not redirect it)

JS is client side, so Google will most likely not see it, which would produce the effect of users seeing a different page than gbot.

If you do use JS, you would probably be best of using an external file. As lazerzubb mentioned, just because they don't parse JS, doesn't mean they can't identify a redirect embedded in the page.