<?php

$strs = ['Connection variable = new DBConnection', 'variable = new DBConnection', '//Connection variable = new DBConnection', '//variable = new DBConnection'];
$rx = '~^(\s*//)?(?:\s*Connection\s+)?(.+?)\s*=\s*new\s+DBConnection~';
foreach ($strs as $s) {
	echo "$s:\n";
	if (preg_match($rx, $s, $m)) {
		if (empty($m[1])) {
			echo "FOUND:" . $m[0] . "\n--------------\n";
		}
	} else {
		echo "NOT FOUND\n--------------\n";
	}
}