问题
I have just migrated a site to a new domain (with new design) and am redirecting from the old site to the new with .htaccess and redirect 301. Since the new site is quite different, I'm concerned that users might be disoriented. Is there a way to have a popup on the new site that users get only if they have been redirected from the old site? Have been searching on this but keywords seem to lead only to stuff on popup redirects to another site.
回答1:
I can think of several ways to do it:
Redirect in the 301 to another page (www.blah.com/tour instead of www.blah.com) and there i would put the logic to show the popup
Redirect in the 301 to another page and there set a cookie and redirect to the original page. Then, add logic to the original page to show the popup if the cookie is present (and delete the cookie)
Check the referrer in the new site and if it matches the old one, show the popup
回答2:
Your problem boils down to detecting a request that has come via a 301 redirect - popups and usability are a separate (simpler?!) issue.
Unfortunately, detecting a 301 redirect is one of those inexact things that requires a mixture of techniques to get near to 100%. I say near, but never quite there - a bit like browser detection.
One option is to append a querystring (GET) parameter to the redirected URL, e.g.
www.example.com/LandingPage.html?isRedirected=true
You could also set the same info in a cookie (but won't work if cookies are disabled or cleared).
Another option is checking the Referrer header - but again, these may differ based on browser implementation and can be faked, although if someone's faking a redirect I don't think you need to worry about guiding them through your new design!
来源：https://stackoverflow.com/questions/11332270/how-to-do-popup-on-new-site-for-301-redirected-users