Show a message at specific times on a specific day - php

Question

How can I insert a specific minute into the following to show a message:
if ($current_day == "Monday") {
if ($current_time >= 15 && $current_time <= 16) {
echo "message";
}
}
For example I want "message" to show at 3:45 or 15:45 and not between the 15th and 16th hour.

Answer 1

I figured out how to do it with javascript:
// Sunday is 0 Monday is 1 and so on
// January is 0 February is 1 and so on
var Digital=new Date()
var month=Digital.getUTCMonth()
var day=Digital.getUTCDate()
var year=Digital.getUTCFullYear()
var hours=Digital.getUTCHours()
var minutes=Digital.getUTCMinutes()
if (month==2&&day==16&&year==2015&&hours==01&&minutes==30 || hours==01&&minutes==45 || hours==01&&minutes==47)
document.write('<b>message here</b>')
else if (month==2&&day==17&&year==2015&&hours==01&&minutes==30 || hours==01&&minutes==45 || hours==01&&minutes==47)
document.write('<b>message 2 here</b>')
else
document.write('<b></b>')
Works perfectly no matter what timezone you're in. There's probably a less crazy way to do this but this is what I have so far.

Answer 2

In order to show a message at exactly 3:45 AM and again at 3:45 PM, you could try this:
$current_day = date('l');
$current_time = date('G:i');
if ($current_day == "Monday") {
if ($current_time == '03:45' || $current_time == '15:45') {
echo "message";
}
}
Or a little cleaner way (especially if you wanted to include a longer list of times):
if (date('l') == "Monday") {
if (in_array(date('G:i'), array('03:45','15:45')) {
echo "message";
}
}
EDIT: To specify a timezone, try inserting this line before either of the above pieces of code:
date_default_timezone_set('America/Los_Angeles');
Where 'America/Los_Angeles' could be any supported string representing your desired timezone from this page of the PHP manual: http://php.net/manual/en/timezones.php