使用JavaScript修改Facebook共享内容

Question

I've been successfully using the Sharrre plugin to add a Facebook share button to a page but I now need to change the title and description of the shared link.

I believe this was possible in the past before Facebook updated sharer.php, with the new version no longer accepting parameters for title, etc. I can change the og:title attribute content via JavaScript but when Facebook requests the page these changes are (obviously) not present.

How are sites like Buzzfeed accomplishing this with their quizzes, where the outcome is shared?

Answer 1

You need to detect the Facebook scraper server side, they use unique User Agent string.

I use this one

preg_match('/facebookexternalhit/i', $_SERVER['HTTP_USER_AGENT'])

Based on this, change og:title and og:description, when FB scrapes your website it will see changed params.