How can regular expressions be used to convert dates in the format "0000-00-00" to a usable format in PHP?

Regular expressions can be used to match and extract the individual components of the date (year, month, day) from the "0000-00-00" format. Once these components are extracted, they can be rearranged into a format that is usable in PHP, such as "YYYY-MM-DD" or any other desired format. This can be achieved using the preg_match function in PHP to extract the date components and then concatenating them in the desired order.

$date = "2022-12-31";
$pattern = "/(\d{4})-(\d{2})-(\d{2})/";
if (preg_match($pattern, $date, $matches)) {
    $usable_date = $matches[1] . "-" . $matches[2] . "-" . $matches[3];
    echo $usable_date; // Output: 2022-12-31
}