Help with regex

I have a preg_match and it is supposed to flag if my date isn't in MM-YYYY format. Here is my code

if 
  (!empty($_POST['StartDate'][$row]) && !preg_match('/^(0[1-9]|1[0-2]) [-] (19|20)\d{2}$/',$_POST['Startdate'][$row]))
  {echo '<b>One of your Start Date columns is not in the proper format. Make Sure it is MM-YYYY<br/>';$dataOK=FALSE;}

Code (markup):

what did i do wrong? Please Help

 

(!empty($_POST['StartDate'][$row]) && !preg_match('/^(0[1-9]|1[0-2])\s*\-\s*(19|20)\d{2}$/',$_POST['Startdate'][$row]))

 

Alternatively you could do (make sure date is not empty)

$rowtime = strtotime($_POST['StartDate'][$row]);
$newstr = date("m-d-Y", $rowtime);

 

Yeah, I'd suggest that, but I wasn't sure if strtotime works with an mm-yyyy format (without day).