Comparing Date

billhobbs

I'm trying to write a script that will compare a child's birthdate to a cutoff date. If the child is born before the cutoff date the they are OK if they are born after the cutoff date then I want a message letting them know they they are not old enough. I think i'm in the ball park but it isn't working correctly.

 $birthDate = "2009-09-03";// Child's Birthday
echo "Birth Date: $birthDate<br>"; 
  $cutoffDate = "2010-09-03"; // Cut off date
echo "Cutoff Date: $cutoffDate<br>";
  $lastDate = "2011-09-03"; //Last day accepting applications
echo "Last Date: $lastDate<br>";

 if($birthdDate >= $cutoffDate){
echo "<br>You are eligible.";
 }else{
echo "<br>You are not eligible, because your child must be 1 year old on or before $lastDate";
 }

bradgrafelman

You can't perform a numerical comparison on two strings (well you can, but the result is pretty much meaningless... is 'banana' greater than 'canon', or 'watermelon' less than 'zookeeper' ?).

Instead, use something like [man]strtotime/man or [man]mktime/man to convert the date(s) into an integer representation (namely a UNIX timestamp). That way, you can compare two integers.

billhobbs

Should this work then?

$birthDate = "2010-09-05";// Child's Birthday
echo "Birth Date: $birthDate<br>"; 
  $cutoffDate = "2010-09-03"; // Cut off date
echo "Cutoff Date: $cutoffDate<br>";
  $lastDate = "2011-09-03"; //Last day accepting applications
echo "Last Date: $lastDate<br>";

 if (strtotime($birthdate) >= strtotime($cutoffDate)){
echo "<br>You are eligible.  $cutoffDate";
 }else{
echo "<br>You are not eligible, because your child must be 1 year old on or before $lastDate.";
 }

bradgrafelman

Probably, yes... did you test it yourself?

billhobbs

Yes, but I tested the other one and it seemed to give me the same results. I just wanted to make sure I wasn't doing something wrong that would pop up later as I'm using the script.