Calculate business days

Question

I need a method for adding \"business days\" in PHP. For example, Friday 12/5 + 3 business days = Wednesday 12/10.

At a minimum I need the code to understand weekend

Answer 1

Here is a function for adding buisness days to a date

 function add_business_days($startdate,$buisnessdays,$holidays,$dateformat){
  $i=1;
  $dayx = strtotime($startdate);
  while($i < $buisnessdays){
   $day = date('N',$dayx);
   $date = date('Y-m-d',$dayx);
   if($day < 6 && !in_array($date,$holidays))$i++;
   $dayx = strtotime($date.' +1 day');
  }
  return date($dateformat,$dayx);
 }

 //Example
 date_default_timezone_set('Europe\London');
 $startdate = '2012-01-08';
 $holidays=array("2012-01-10");
 echo '
Start date: '.date('r',strtotime( $startdate));
 echo '
'.add_business_days($startdate,7,$holidays,'r');

Another post mentions getWorkingDays (from php.net comments and included here) but I think it breaks if you start on a Sunday and finish on a work day.

Using the following (you'll need to include the getWorkingDays function from previous post)

 date_default_timezone_set('Europe\London');
 //Example:
 $holidays = array('2012-01-10');
 $startDate = '2012-01-08';
 $endDate = '2012-01-13';
 echo getWorkingDays( $startDate,$endDate,$holidays);

Gives the result as 5 not 4

Sun, 08 Jan 2012 00:00:00 +0000 weekend
Mon, 09 Jan 2012 00:00:00 +0000
Tue, 10 Jan 2012 00:00:00 +0000 holiday
Wed, 11 Jan 2012 00:00:00 +0000
Thu, 12 Jan 2012 00:00:00 +0000
Fri, 13 Jan 2012 00:00:00 +0000 

The following function was used to generate the above.

     function get_working_days($startDate,$endDate,$holidays){
      $debug = true;
      $work = 0;
      $nowork = 0;
      $dayx = strtotime($startDate);
      $endx = strtotime($endDate);
      if($debug){
       echo '
get_working_days
';
       echo 'startDate: '.date('r',strtotime( $startDate)).'
';
       echo 'endDate: '.date('r',strtotime( $endDate)).'
';
       var_dump($holidays);
       echo '
Go to work...';
      }
      while($dayx <= $endx){
       $day = date('N',$dayx);
       $date = date('Y-m-d',$dayx);
       if($debug)echo '
'.date('r',$dayx).' ';
       if($day > 5 || in_array($date,$holidays)){
        $nowork++;
     if($debug){
      if($day > 5)echo 'weekend';
      else echo 'holiday';
     }
       } else $work++;
       $dayx = strtotime($date.' +1 day');
      }
      if($debug){
      echo '
No work: '.$nowork.'
';
      echo 'Work: '.$work.'
';
      echo 'Work + no work: '.($nowork+$work).'
';
      echo 'All seconds / seconds in a day: '.floatval(strtotime($endDate)-strtotime($startDate))/floatval(24*60*60);
      }
      return $work;
     }

    date_default_timezone_set('Europe\London');
     //Example:
     $holidays=array("2012-01-10");
     $startDate = '2012-01-08';
     $endDate = '2012-01-13';
//broken
     echo getWorkingDays( $startDate,$endDate,$holidays);
//works
     echo get_working_days( $startDate,$endDate,$holidays);

Bring on the holidays...