Question

For a content with the format:

KEY=VALUE

like:

LISTEN=I am listening.

I need to do some replacing using regex. I want this regular expression to replace anything before the = with $key (making it have to be from beginning of line so a key like ‘EN’ wont replace a key like “TOKEN”.

Here’s what I’m using, but it doesn’t seem to work:

$content = preg_replace('~^'.$key.'\s?=[^\n$]+~iu',$newKey,$content);

Answer 1

$content = "foo=one\n"
         . "bar=two\n"
         . "baz=three\n";

$keys = array(
    'foo' => 'newFoo',
    'bar' => 'newBar',
    'baz' => 'newBaz',
);
foreach ( $keys as $oldKey => $newKey ) {
    $oldKey = preg_quote($oldKey, '#');
    $content = preg_replace("#^{$oldKey}( ?=)#m", "{$newKey}\\1", $content);
}

echo $content;

Output:

newFoo=one
newBar=two
newBaz=three