Regex activate multi line in php -

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• php preg_replace regex matches multiple lines 2 answers

please tell me how activate multi line functionality..and explain me how work. (?m) or /m ?

$subject = "the brown fox jump bla on lazy  dog ..bla bla bla"; $matching = preg_match_all($regex1, $subject, $m); $regex1 = '(?m)/^bla$\b/i'; print_r($m); 

what use , where? ...(?m) or /m ?

what use , where? ...(?m) or /m

you can use either of them cannot use \b (word boundary) after anchor $. use:

$regex1 = '/^bla$/im';  $subject = "the brown fox jump bla on lazy  dog ..bla bla bla";  preg_match_all($regex1, $subject, $m); print_r($m); 

and need declare regex before can use it.

however none of lines have text bla hence regex fail match anything.

looking @ examples may need:

$regex1 = '/\bbla$/im'; 

which match line #1 , line #3.