Q:

Using date("H"); to define minutes PHP

What I want to achieve is to make a div appear at a set time, which I've achieved (go me), My problem is with my current code I can only set the time in hours. I'd like to be able to set it in hours/minutes. 
For example make the div appear between 9am and 10:30am. (Currently, I can only make it appear on "hours" only, so 9am to 10am for example.)
Here is where I set the time:
date_default_timezone_set('Europe/London');
$currentHour = date("H");
$day = date("1");
$nineAlertStart = 9;
$nineAlertEnd = 10;

Here is the function to display div on set time:
if ($currentHour >= $nineAlertStart && $currentHour < $nineAlertEnd){
          // If we are, set our class to off.
        $ninealert = 'timeOn';
  } else {
        // Otherwise, set our class to off.
        $ninealert = 'timeOff';
  }

And finally here is my output to display
<div class="alert <?php echo $ninealert; ?>">
    Jade
</div>

I know not all of this code is needed but I thought it might help understand what I'm trying to achieve.

A:

Try the following and see if this works for you
date_default_timezone_set('Europe/London');
$currentTime = date("Gi");
$day = date("1");
$nineAlertStart = 900;
$nineAlertEnd = 1030;

if ($currentTime >= $nineAlertStart && $currentTime < $nineAlertEnd){
      // If we are, set our class to off.
    $ninealert = 'timeOn';
} else {
    // Otherwise, set our class to off.
    $ninealert = 'timeOff';
}

