Leap Year

[latemodern]

Hi,

I am trying to write a script that corrects the date if the finish time (of a shift) goes past midnight. It works for every scenario apart from the 28th of February on a leap year. I have tried to use the date(L, ) function to correct this but it doesn't appear to be working. Any ideas? The script is below.

Many thanks

//adjust the date if finish time is past midnight
if (($start_hour > $finish_hour) && ($finish_hour < 6)){
if($d == 31 || ($d == 30 && $m == (4 || 6 || 9 || 11)) || (($m == 2) && ($d == 28) && (date( 'L', $y ) == 0)) || (($m == 2) && ($d == 29) && (date( 'L', $y ) == 1))){
$dtemp = 1;
if($m == 12){
$mtemp = 1;
$ytemp = ($y + 1);
} else {
$mtemp = ($m + 1);
$ytemp = $y;
}
} else {
$dtemp = ($d +1);
$mtemp = ($m);
$ytemp = ($y);
}
$date = $ytemp.'-'.$mtemp.'-'.$dtemp;
}
$finish = $date.' '.$finish_hour. ':' .$finish_min.':00';

			}//end of if hours and mins

[MarkR]

Yeuck!

Quite frankly, I don't think this is not the right way of approaching this problem.

Personally, I would do the following:

1. Convert the date/time to a unix timestamp (which is the normal PHP way)
2. Add the appropriate number of hours / minutes etc to it
3. Convert it back into a date

This will work correctly in every case, and be a lot more concise and maintainable.

The only problem is that PHP does not have a standard function for converting a string into a date - you'll have to write that yourself.

But any application which handles dates is going to need one of those anyway - write a single function and reuse it throughout, making sure it will parse dates in the format that you expect from your country's conventions (and reject invalid ones).

Mark

[laserlight]

The only problem is that PHP does not have a standard function for converting a string into a date - you'll have to write that yourself.

It does, actually. [man]strtotime/man

[MarkR]

laserlight wrote:

It does, actually. [man]strtotime/man

No, I'm afraid it doesn't.

strtotime, while it may be useful in some cases, does not convert a date into a timestamp in a (typically) usable way.

It's for doing the conversions according to various English rules, like "tomorrow". It's not useful for parsing a strict format into a valid date.

Moreover, I can't see how to specify the date format.

Mark

[laserlight]

strtotime, while it may be useful in some cases, does not convert a date into a timestamp in a (typically) usable way.

Obviously for certain formats that can be correctly interpreted in two different ways using strtotime() may result in unexpected timestamps. For the OP's case I find the code snippet rather opaque, so it is better to make such functions known than to assume that more manual means of conversion (e.g. [man]mktime/man ) must be used.

Moreover, I can't see how to specify the date format.

By using the timestamp with some other timestamp-to-date function, of course.

[Weedpacket]

And depending on how the shift start/end times are being calculated and stored (I don't get how this is being done here); if it's a matter of the end time being a certain number, say 8, of hours after the start time, then $end_time = strtotime('+8 hours', $start_time), where both variables contain Unix timestamps.

I'll agree with MarkR; there's no point reinventing this particular wheel since PHP has much more robust ones already available. I'd also agree with laserlight that strtotime() is quite a bit more useful than MarkR claims; at the moment, though, it would be too much hassle to reassemble all these bits and pieces into a string just to convert it into a timestamp (but if this particular wheel wasn't being reinvented, this wouldn't be an issue).