How do you consolidate repeated code within functions? - php

Question

I tried to create a class to consolidate the following functions but I don't fully understand the approach, how would I approach the following functions to remove the need to query the DB on each occasion an just call the separate echo blocks?
function get_pages_new() {
$cxn = mysqli_connect('localhost', 'root', '', 'northern') or die(mysqli_error($cxn));
$query = ("SELECT * FROM `pages` ORDER BY `page_id` ASC") or die(mysqli_error($cxn));
$getnews = mysqli_query($cxn, $query);
while ($row = mysqli_fetch_assoc($getnews)) {
$page_id = $row['page_id'];
$page_title = $row['page_title'];
$admin = $row['admin_only'];
echo "<li>$page_title</li>";
}
};
function get_pages_edit() {
$cxn = mysqli_connect('localhost', 'root', '', 'northern') or die(mysqli_error($cxn));
$query = ("SELECT * FROM `pages` ORDER BY `page_id` ASC") or die(mysqli_error($cxn));
$getnews = mysqli_query($cxn, $query);
while ($row = mysqli_fetch_assoc($getnews)) {
$page_id = $row['page_id'];
$page_title = $row['page_title'];
$admin = $row['admin_only'];
echo "<li>$page_title</li> ";
}
};
function get_pages_delete() {
$cxn = mysqli_connect('localhost', 'root', '', 'northern') or die(mysqli_error($cxn));
$query = ("SELECT * FROM `pages` ORDER BY `page_id` ASC") or die(mysqli_error($cxn));
$getnews = mysqli_query($cxn, $query);
while ($row = mysqli_fetch_assoc($getnews)) {
$page_id = $row['page_id'];
$page_title = $row['page_title'];
$admin = $row['admin_only'];
echo "<li>$page_title</li>";
}
};
Thanks

Answer 1

Pass in a parameter that contains the link:
function get_pages($link) {
$cxn = mysqli_connect('localhost', 'root', '', 'northern') or die(mysqli_error($cxn));
$query = ("SELECT * FROM `pages` ORDER BY `page_id` ASC") or die(mysqli_error($cxn));
$getnews = mysqli_query($cxn, $query);
while ($row = mysqli_fetch_assoc($getnews)) {
$page_id = $row['page_id'];
$page_title = $row['page_title'];
$admin = $row['admin_only'];
echo "<li><a href='".$link."?page_id=".$page_id."'>".$page_title."</li></a>";
}
};
Where $link is add_page.php, edit_page.php or remove_page.php. Unless I've misread your code and each function is running a seperate query, this should work :)

Answer 2

$Create a method for that instead of a class:
function extractIdTitleAdminFromEntry($entry) {
return [
'page_id' => $entry['page_id'],
'page_title' => $entry['page_title'],
'admin_only' => $entry['admin_only'],
];
}
Now you can do this inside your while loops:
list($page_id, $page_title, $admin_only) = extractIdTitleAdminFromEntry($row);
You can even modify it such that the list of properties is dynamic:
function extractIdTitleAdminFromEntry($entry, $properties) {
$values = [$key];
foreach ($properties as $key) {
$values[$key] = isset($entry[$key] ? $entry[$key] : null;
}
return $values;
}
list($page_id, $page_title, $admin_only) = extractIdTitleAdminFromEntry(
$row,
['page_id', 'page_title', 'admin_only']
);