Lets say I have the string: "Test [[1294]] example"
How could I do a preg_replace() that would extract the number from the double brackets?
Could someone please advise me to what the (Greedy) expression for getting that number would be? -it'll always be a integer within double brackets.
Thanks alot.
You might want to check out a tutorial.
If you want to "extract" the number, there is no need for preg_replace. Use preg_match or preg_match_all (if there are multiple occurrences) instead:
preg_match('/\[\[(\d+)\]\]/', $input, $matches);
$integer = $matches[1];
or
preg_match_all('/\[\[(\d+)\]\]/', $input, $matches);
$integerArray = $matches[1];
If instead of "extract" you actually meant something like "how can I preg_replace this term and use the extracted integer number", you can use the same regular expression and refer to the captured integer, using $1:
$output = preg_replace('/\[\[(\d+)\]\]/', 'Found this integer -> $1 <-', $input);
Which would result in:
Test Found this integer -> 1294 <- example
You would use preg_match(), not preg_replace():
$subject = 'Test [[1294]] example';
preg_match('/\[\[(\d+)\]\]/', $subject, $match);
echo $match[1];