Function to check if a string is a date
If that's your whole string, then just try parsing it:
if (DateTime::createFromFormat('Y-m-d H:i:s', $myString) !== false) { // it's a date}
Easiest way to check if a string is a date:
if(strtotime($date_string)){ // it's in date format}
Here's a different approach without using a regex:
function check_your_datetime($x) { return (date('Y-m-d H:i:s', strtotime($x)) == $x);}