$re = '/^\$ml\$(?=([^$]*\$){2}[^$]*$)[a-fA-F0-9$]{1,200}$/';
$str = '$ml$35460$93a94bd24b5de64d79a5e49fa372827e739f4d7b6975c752c9a0ff1e5cf72e05$752351df64dd2ce9dc9c64a72ad91de6581a15c19176266b44d98919dfa81f0f96cbcb20a1ffb400718c20382030f637892f776627d34e021bad4f81b7de8222';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php