Regex to get the Facebook Page ID from a given URL

gistfile1.rb

# Matches patterns such as:
#    https://www.facebook.com/my_page_id => my_page_id
#    http://www.facebook.com/my_page_id => my_page_id
#    http://www.facebook.com/#!/my_page_id => my_page_id
#    http://www.facebook.com/pages/Paris-France/Vanity-Url/123456?v=app_555 => 123456
#    http://www.facebook.com/pages/Vanity-Url/45678 => 45678
#    http://www.facebook.com/#!/page_with_1_number => page_with_1_number
#    http://www.facebook.com/bounce_page#!/pages/Vanity-Url/45678 => 45678
#    http://www.facebook.com/bounce_page#!/my_page_id?v=app_166292090072334 => my_page_id
#    http://www.facebook.com/my.page.is.great => my.page.is.great

/(?:https?:\/\/)?(?:www\.)?facebook\.com\/(?:(?:\w)*#!\/)?(?:pages\/)?(?:[\w\-]*\/)*([\w\-\.]*)/

Matching fails if url contains closing slash, like https://www.facebook.com/my_page_id/
The regex below is more simpler working solution:

(?:https?:\/\/)?(?:www\.)?facebook\.com\/(?:.+\/)*([\w\.\-]+)

^(?:https?:\/\/)?(?:www\.|m\.|touch\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?:(?:\w)*#!\/)?(?:pages\/)?(?:[\w\-]*\/)*?(\/)?([^/?\s]*)(?:/|&|\?)?.*$
support also m.facebook.com, touch.facebook.com, fb.me, fb.com

example :
https://www.facebook.com/TrollsdeGeek/videos/1612020065488125/
https://www.facebook.com/Φc?ref=hl
http://m.facebook.com/Φc?ref=hl
http://www.facebook.com/Φc/?ref=hl
http://www.facebook.com/pages/Φc/1234?ref=hl
http://www.facebook.com/pages/Φc/1234/?ref=hl
http://www.facebook.com/mypageusername?ref=hl
http://touch.facebook.com/mypageusername?ref=hl
https://www.facebook.com/mypageusername?ref=hl
http://www.facebook.com/pages/Vanity-Url/12345678?ref=hl
https://www.facebook.com/pages/Vanity-Url/12345678?ref=hl
http://www.facebook.com/pages/%CE%A4%CE%91-%CE%A6%CE%A1%CE%9F%CE%A5%CE%A4%CE%91-%CE%A4%CE%9F%CE%A5-%CE%94%CE%91%CE%A3%CE%9F%CE%A5%CE%A3/145298928829093
http://www.facebook.com/pages/ΤΑ-ΦΡΟΥΤΑ-ΤΟΥ-ΔΑΣΟΥΣ/145298928829093
https://www.facebook.com/Babies.Fan.Page
https://www.facebook.com/pages/Babies.Fan.Page/121166161229757
https://www.facebook.com/pages/GHOST-Caf%C3%A9/627191887397533?fref=ts

missing https://www.facebook.com/profile.php?id=123456789

@BastienMottier
Just a little mistake. Unescaped slash at the end.
This below works better
^(?:https?:\/\/)?(?:www\.|m\.|touch\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?:(?:\w)*#!\/)?(?:pages\/)?(?:[\w\-]*\/)*?(\/)?([^/?\s]*)(?:\/|&|\?)?.*$

@Raphhh
this one below also works for profile.php
^(?:https?:\/\/)?(?:www\.|m\.|touch\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?:(?:\w)*#!\/)?(?:pages\/)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^/?\s]*)(?:\/|&|\?)?.*$

@lekiend There was one more missing slash.

Also, this below disallows host URLs ending in a slash with no profile e.g. https://www.facebook.com, http://fb.me, https://m.facebook.com/

^(?:https?://)?(?:www.|m.|touch.)?(?:facebook.com|fb(?:.me|.com))/(?!$)(?:(?:\w)#!/)?(?:pages/)?(?:[\w-]/)?(?:/)?(?:profile.php?id=)?([^\/?\s])(?:/|&|?)?.*$

where did u guys know how to write all these?

doesnt work for Unicode containing pages, like this:

https://www.facebook.com/საწარმო-SabaDesign-927047470710565/?ref=safrghbeდფწერგ

Props for all contributers!!
Everything incorporated above, with just one more forgotten escape character added, gives me this:

/^(?:https?:\/\/)?(?:www\.|m\.|touch\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?!$)(?:(?:\w)*#!\/)?(?:pages\/)?(?:photo\.php\?fbid=)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^\/?\s]*)(?:\/|&|\?)?.*$/

Which works GREAT (yay), except when the url has arguments after the profile.php?id= or fbid= part like these urls:

https://www.facebook.com/profile.php?id=114376375296751&fref=pb&hc_location=friends_tab
returns 114376375296751&fref=pb&hc_location=friends_tab instead of 114376375296751

and

https://www.facebook.com/photo.php?fbid=114376375296751&set=a.114376371963418.13845.114375165296872&type=1&theater
returns 114376375296751&set=a.114376371963418.13845.114375165296872&type=1&theater

Someone care to snip everything off after the first &?

/^(?:https?://)?(?:www.|m.|touch.)?(?:facebook.com|fb(?:.me|.com))/(?!$)(?:(?:\w)#!/)?(?:pages/)?(?:photo.php?fbid=)?(?:[\w-]/)?(?:/)?(?:profile.php?id=)?([^\/?\&\s])(?:/|&|?)?.*?$/

this should exclude the & as well

Ayal's alternative didn't work for me. It worked when I got hoofdletterj's answer and added & before \s (Ayal's partial answer):

/^(?:https?:\/\/)?(?:www\.|m\.|touch\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?!$)(?:(?:\w)*#!\/)?(?:pages\/)?(?:photo\.php\?fbid=)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^\/?&\s]*)(?:\/|&|\?)?.*$/

I want to display the post's images of Facebook on my website by just copy the address of the image is there any regex for that i have use the above regex but it doesn't help me
preg_match_all('/(https?://\S+.(?:jpg|png|gif))+/', $string, $match);
i am using this regex but it display all the other images except Facebook''s images

I updated the regex to match even mbasic:

^(?:https?:\/\/)?(?:www\.|m\.|touch\.|mbasic\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?!$)(?:(?:\w)*#!\/)?(?:pages\/)?(?:photo\.php\?fbid=)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^\/?&\s]*)(?:\/|&|\?)?.*$

It works for urls like:

https://mbasic.facebook.com/BMW/?refid=46&__xts__%5B0%5D=12.%7B%22unit_id_click_type%22%3A%22graph_search_results_item_tapped%22%2C%22click_type%22%3A%22result%22%2C%22module_id%22%3A2%2C%22result_id%22%3A22893372268%2C%22session_id%22%3A%22e4709b011e94ec8207a44ffedd1d2901%22%2C%22module_role%22%3A%22ENTITY_PAGES%22%2C%22unit_id%22%3A%22browse_rl%3Ab2718be4-bbd0-4764-9c31-6908c431daa2%22%2C%22browse_result_type%22%3A%22browse_type_page%22%2C%22unit_id_result_id%22%3A22893372268%2C%22module_result_position%22%3A0%7D

There's also mobile.facebook.com, so here's the new regex:

^(?:https?:\/\/)?(?:www\.|m\.|mobile\.|touch\.|mbasic\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?!$)(?:(?:\w)*#!\/)?(?:pages\/)?(?:photo\.php\?fbid=)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^\/?&\s]*)(?:\/|&|\?)?.*$

Which can match stuff like:

https://mobile.facebook.com/BMW/

https://www.facebook.com/profile.php?id=100015670091629

(?:https?:\/\/)?(?:www\.|m\.|mobile\.|touch\.|mbasic\.)?(?:facebook\.com|fb(?:\.me|\.com))\/(?!$)(?:(?:\w)*#!\/)?(?:pages\/|pg\/)?(?:photo\.php\?fbid=)?(?:[\w\-]*\/)*?(?:\/)?(?:profile\.php\?id=)?([^\/?&\s]*)(?:\/|&|\?)?.*

This will match /pg/ URL as weel
https://m.facebook.com/pg/DwayneTheRockJohnsonFanClub/photos/
...................................................^

@https://www.facebook.com/profile.php?id=100073611427332&mibextid=LQQJ4d