Telling via php to redirect with an if statement and search engine spiders?

Almost all of my web sites pages are user accessed and if not a user and not logged in they cannot access the pages at all.

Will the search e开发者_运维技巧ngine spiders still be able to list, crawl and index these user pages as they won't be logging in?

Is there a better way using this system of getting better indexing?

If you have non-user related content and you want search engines to crawl it you should enable them accessing it without login.

A spider doesn't login, so no, it can't see protected pages. You should also not try to make those pages visible to spiders and not to visitors who are not logged in, search engines will put a penalty on your site for that or even stop indexing it.

You could however show an excerpt of the page to users who aren't logged in, like the first X words. Spiders crawling the page will be able to read that text.