HTML file coding (filename form.html or whatever you choose):

 <h2>PHP exercise 3: Birthday calculator</h2>
<p><form action="exercise3process.php" method="post">
Enter your birthday in this format: DD/MM/YYYY e.g. 20/08/1980 

<input type="text" name="day" size="2"> / <input type="text" name="month" size="2"> / <input type="text" name="year" size="4"> <br>
<input type="submit" value="Launch!">
</form>
</p>
<p> <a href="exercise3source.txt">See source code here </a></p>



PHP File coding (filename exercise2process.php):

<?php

// retrieve form data

$day= $_POST['day'];
$month= $_POST['month'];
$year = $_POST['year'];

//error check
if ($month>12) {
echo "Your month number bigger than 12! <br>";
}

//turn what you have entered into a date object:

$date=$year."-".$month."-".$day;
$birthdate=date_create($date);
//get today's date
$today=date_create();

// use it
echo "You were born on the ".$day."th day of the ".$month."th month, in the year ".$year.". <br>";
echo date_format($birthdate,"Y/m/d")."<br>";

$interval = date_diff($today, $birthdate);
echo "You have lived for ".$interval->format('%a')." days.<br>";

//star sign checker
$starsign = array
  (
  array("Aries",3,21,4,20),
  array("Taurus",4,21,5,21),
  array("Gemini",5,22,6,21),
  array("Cancer",6,22,7,23),
array("Leo",7,24,8,23),
array("Virgo",8,24,9,23),
array("Libra",9,24,10,23),
array("Scorpio",10,24,11,22),
array("Sagittarius",11,23,12,22),
array("Capricorn",12,23,1,20),
array("Aquarius",1,21,2,19),
array("Pisces",2,20,3,20),

  );
  
  for ($x=0;$x<=11;$x++) {
if ($month==$starsign[$x][1] && $day>=$starsign[$x][2]) {
echo "Your star sign is ".$starsign[$x][0];
}
if ($month==$starsign[$x][3] && $day<=$starsign[$x][4]) {
echo "Your star sign is ".$starsign[$x][0];
}


}

// echo $interval->format('%R%a days');
 





?>