PHP mulitiple checkboxes - php

Question

I am stuck on a script and need another pair of eyes to see if I am missing something. The script is for a bookshop. When a student number is in-putted and searched for the student is displayed with the books that he is suppose to get for each subject. The student, course and book data comes from a MySQL database.
This is all done with this script:
<?php
if (isset($_POST['submit'])){
$btnClick = $_POST['submit'];
switch($btnClick){
case "Logout" :
session_destroy();
header("location:index.php");
break;
case "Search" :
$Validate = $_POST['txtStud'] ;
$StudNr = ValidateTxt($Validate);
$showStud = findStud($StudNr);
$cid = $showStud[4];
$showBooks = findBooks($cid);
echo "<form action='issue_book.php' method='post'>";;
echo "<table class='table3'>";
echo "<tr>";
echo "<td>" . $showStud[0] . " " . $showStud[1] . " " . $showStud[2] ."</td>";
echo "</tr>";
echo "<tr><td></td><td>" . $showStud[3] . "</td></tr>";
$array_count = count($showBooks);
$num = 0;
while ($num != $array_count) {
$bookNum = $showBooks[$num]['bid'];
echo $bookNum . "<br>";
echo "<tr><td>" . $showBooks[$num]['bid'] . "</td>" . "<td>" . $showBooks[$num]['bname'] . "</td>" ;
echo "<td><input type='checkbox' name='booknum[]' value='<?php echo $bookNum; ?>'></td></tr>";
$num++;
}
echo "</table>";
echo "<br>";
echo "<table class = 'table3'>";
echo "<tr><td></td><td><input type='submit' name='submit' value='Issue'></td>
<td><input type='submit' name='submit' value='Clear'></td></tr>";
echo "</form>";
break;
case "Issue":
$mybooks = $_POST['booknum'];
$h = count($mybooks);
echo $h . "<br>";
print_r ($mybooks);
break;
}
}
?>
At the bottom of the dynamic created data there is 2 buttons. When I click on the Issue button I am presented with this data.
This comes from the code as it is in the script at this moment. I want to send the data from here to the database.
Array ( [0] => [1] => [2] => )
An empty array?? Not sure what happened to the names that I assigned each check box??
I tried to adapt my script according to this forum post Check box link
I am not sure where I am missing something.

Answer 1

This is because you have a syntax error here
echo "<td><input type='checkbox' name='booknum[]' value='<?php echo $bookNum; ?>'></td></tr>";
^php tags are opened ^
You are already printing your table inside php tags, you cannot open other tags
value='<?php echo $bookNum; ?>
This is why your array's values are empty but keys exists. You just need to concatenate
echo "<td><input type='checkbox' name='booknum[]' value='".$bookNum."'></td></tr>";