PHP自动生成月历代码

/* 
  Function Written by Nelson Neoh @3/2004. 
  For those who wants to utilize this code, please do not remove this remark. 
  If you have done any enhancement to this code, please post the copy at http://www.dev-club.com PHP board. Thank you.

  Function usage: calendar(Month,Year)
  */
  function calendar($MM,$YYYY){
  if($MM=="") $MM = date("m");
  if($YYYY=="") $YYYY = date("Y");
  if(checkdate($MM,1,$YYYY)){
  $stringDate = strftime("%d %b %Y",mktime (0,0,0,$MM,1,$YYYY));
  $days = strftime("%d",mktime (0,0,0,$MM+1,0,$YYYY));
  $firstDay = strftime("%w",mktime (0,0,0,$MM,1,$YYYY));
  $lastDay = strftime("%w",mktime (0,0,0,$MM,$days,$YYYY));
  $printDays = $days;
  $preMonth = strftime("%m",mktime (0,0,0,$MM-1,1,$YYYY));
  $preYear = strftime("%Y",mktime (0,0,0,$MM-1,1,$YYYY));
  $nextMonth = strftime("%m",mktime (0,0,0,$MM+1,1,$YYYY));
  $nextYear = strftime("%Y",mktime (0,0,0,$MM+1,1,$YYYY));
  print("");
  print("");
  print("");
  print("");
  print("");
  print("");
  $currentDays = 1;
  for($a=1;$a<=5;$a++){
  print("");
  $diffDays = $firstDay-$lastDay;
  if($firstDay>$lastDay && $currentDays ==1 && ($diffDays<>1)){
  for($x=$lastDay;$x>=0;$x--){
  $printDays = $days-$x;
  print("");
  }
  for($z=1;$z<$firstDay-$lastDay;$z++){
  print("");
  }
  for($y=$firstDay;$y<7;$y++){
  print("");
  $currentDays++;
  }
  } elseif($firstDay!=0 && $currentDays==1){
  for($z=1;$z<=$firstDay;$z++){
  print("");
  }
  for($y=$firstDay;$y<7;$y++){
  print("");
  $currentDays++;
  }
  } else {
  for($u=1;$u<=7 && $currentDays<=$days;$u++){
  print("");
  $currentDays++;
  }
  }
  print("");
  }
  print("
P
".strftime("%b %Y",mktime (0,0,0,$MM,1,$YYYY))."
N
Sun
Mon
Tue
Wed
Thu
Fri
Sat
$printDays
 
$currentDays
 
$currentDays
$currentDays
");
  }
  }