Time Validator

I need a regular expression that validate time hh:mm:ss. Please guide me

 

Can you share some code so we know what sort of thing will need validating?

 

You can't easily validate it with a regular expression alone. Maybe it's possible, but not worth the effort I'd say.

Instead, try something like this (untested):

if (preg_match('/^(\d{1,2}):(\d{1,2}):(\d{1,2})$/',
   trim($_REQUEST['time']), $matches)
   && $matches[1] < 24
   && $matches[2] < 60
   && $matches[3] < 60)
{
   $valid_time = sprintf('%02d:%02d:%02d',
      $matches[1], $matches[2], $matches[3]);
   echo "<p>Valid time submitted: {$valid_time}</p>";
}
else
   echo "<p>Time was invalid.</p>";

Code (markup):