So I have an interesting problem: I have a string, and for the most part I know what to expect:
http://www.someurl.com/st=????????
Except in this case, the ?'s are either upper case letters or numbers. The problem is, the string has garbage mixed in: the string is broken up into 5 or 6 pieces, and in between there's lots of junk: unprintable characters, foreign characters, as well as plain old normal characters. In short, stuff that's apt to look like this: Nyþ=mî;ëMÝ×nüqÏ
Usually the last 8 characters (the ?'s) are together right at the end, so at the moment I just have PHP grab the last 8 chars and hope for the best. Occasionally, that doesn't work, so I need a more robust solution.
The problem is technically unsolvable, but I think the best solution is to grab characters from the end of the string while they are upper case or numeric. If I get 8 or more, assume that is correct. Otherwise, find the st= and grab characters going forward as many as I need to fill up the 8 character quota. Is there a regex way to do this or will I need to roll up my sleeves and go nested-loop style?
update:
To clear up some confusion, I get an input string that's like this:
[garbage]http:/[garbage]/somewe[garbage]bsite.co[garbage]m/something=[garbage]????????
except the garbage is in unpredictable locations in the string (except the end is never garbage), and has unpredictable length (at least, I have been able to find patterns in neither). Usually the ?s are all together hence me just grabbing the last 8 chars, but sometimes they aren't which results in some missing data and returned garbage.
$var = '†http://þ=www.ex;üßample-website.î;ëcomÝ×ü/joy_hÏere.html'; // test case
$clean = join(
array_filter(
str_split($var, 1),
function ($char) {
return (
array_key_exists(
$char,
array_flip(array_merge(
range('A','Z'),
range('a','z'),
range((string)'0',(string)'9'),
array(':','.','/','-','_')
))
)
);
}
)
);
Hah, that was a joke. Here's a regex for you:
$clean = preg_replace('/[^A-Za-z0-9:.\/_-]/','',$var);