[PHP] extract a line matching a phrase

Question

hello, I want to match a whole line matching a word/phrase on that line! I tried this:

preg_match("/PHRASE/i", $dictionary,$matches);

But I get only the matched word! but I need that whole line! And there more than 15K lines! So I am looking for best way to do it!

thanks in advance!

Answer 1

Just use

^.*PHRASE.*$

^ to match the start of the line

.* to match any number of characters except newlines

PHRASE to match your keyword/phrase

.* as above

$ to match the end of the line.

You might also want to surround your PHRASE with word boundary anchors (if your phrase is indeed a word or words): ^.*\bPHRASE\b.*$ will match only if PHRASE is on its own (and not part of another word like PHRASEBOOK).

So, if you are applying your regex to every single line separately, use

preg_match('/^.*PHRASE.*$/i', $dictionary, $matches)

If you have all your lines inside a long multiline string and want to iterate over all the lines that contain your phrase, use:

preg_match_all('/^.*PHRASE.*$/im', $dictionary, $matches, PREG_PATTERN_ORDER);
for ($i = 0; $i < count($matches[0]); $i++) {
    # Matched text = $matches[0][$i];
}

Note the /m modifier to allow ^ and $ to match at the start and end of each line (instead of just start/end of the string).

Answer 2

Use something like:

$handle = @fopen("file.txt", "r");
if ($handle)
{
    $matches = array();
    while (!feof($handle))
    {
        $buffer = fgets($handle);
        if(stripos($buffer,"mystring") !== false)
        {
            $matches[] = $buffer;
        }
    }
    fclose($handle);
}

Then you can see the results in $matches

Answer 3

try

preg_grep('/whatever/', file('filename'));

file — Reads entire file into an array

preg_grep — Return array entries that match the pattern