PHP reads data from a TXT data, matches the conditions after writing to another TXT file

PHP reads data from a TXT file, matches the conditions after writing to another TXT file
I want to use PHP from a TXT file to read the data, matching the conditions of the write to another TXT file, the code, do not know where the problem, after each execution will only write the last one to meet the criteria (on one), I hope that all meet the conditions, I hope the hero guidance!


$path = ' aa.txt ';

$FP =fopen ($path, "R");


$str = file_get_contents ($path);//Get content
$arr = explode ("\ n", $str);//Branch deposit Array

foreach ($arr as $row)//traverse each row
{
if (Preg_match ("/^ ([a-za-z0-9_\.\-]) +\@ (([a-za-z0-9\-]) +\.) + ([a-za-z0-9]{2,4}) +$/", $row)) {
$path 2 = ' bb.txt ';
$FP 2=fopen ($path 2, "a");
Fwrite ($fp 2, $row. " \ r \ n ");
Fclose ($fp 2);
}
}
Fclose ($FP);
?>

------Solution--------------------
There's no problem with your code.

Why don't you just take out the email, please?

$str = file_get_contents ($path);//Get content
if (Preg_match_all ("/^ ([a-za-z0-9_\.\-]) +\@ (([a-za-z0-9\-]) +\.) + ([a-za-z0-9]{2,4}) +$/m ", $str, $r)) {
File_put_contents (' $path 2, join ("\ n", $r [0]));
}

You can do it.
------Solution--------------------

$arr = explode ("\ n", $str);
Change into
$arr = Preg_split ('/[\\r\\n]+/', $str);

