Question

I’m trying to make all elements from the classlist to display only when they are in common with me and person b. for example if I have classes in position 1,2,5, and I’m on person b’s profile who is in class 9,1,8,17,3, It would display ONLY 1 since they both have 1 in their classlist

_{(source: goawaymom.com)}

I’ve tried a few things like exploding the classlist and giving everything their own variable… Nothing seems to work and I am over complicating everything i try.
Does anyone know any simple ways to do this?

<?php
if ($_SESSION['classlist'] == $user_info['classlist']) {
echo ($user_info['classlist']);

} else {
    echo 'No Common Classes';
}
?>

The above code only displays the classlist when the order of the classlist of person a and b have the same classes in the same order.

Answer 1

array_intersect

For example:

// fetch your results from the database
$myclasses = explode(',', $myrow['classlist']);
$theirclasses = explode(',', $theirrow['classlist']);

$common_classes = array_intersect($myclasses, $theirclasses);

Or in your case: (assuming that both $_SESSION[‘classlist’] and $user_info[‘classlist’] are strings containing comma separated numbers: ‘1,2,3,4,5’)

$myclasses = explode(',', $_SESSION['classlist']);
$theirclasses = explode(',', $user_info['classlist']);
$common_classes = array_intersect($myclasses, $theirclasses);

if (count($common_classes) > 0)
{
    echo '<p>You have the following classes in common.</p>';
    echo '<ul>';
    foreach ($common_classes as $class)
    {
        echo '<li>' . $class . '</li>';
    }
    echo '</ul>';
}
else
{
    echo '<p>Billy no mates :(</p>';
}