PHP - check if cell is empty - php

Question

I'm writing a simple PHP page that is pulling information through into cards.
At the moment my script is hard coding the amount of "linktitle_1, linktitle_2, linktitle_3" etc that are able to be pulled through, at the moment it is 3, and if any of the 3 cells are empty they are still echoed out as empty, and with a comma afterwards.
What I want to do is to be able to print out any from 0-7 items of information. (The appropriate columns are present in the database)
Psuedo code would be something like this:
if (linktitle_1 = empty, linktitle_1_url = empty) {
echo '<p>linktitle_1</p>'}
else {
do nothing
};
I'm looking to do this with both the related links, and the link title sections. So I guess what I need to know is:
How do I escape the echo that these statements are to be inside of?
How do I use an if statement to check if something is empty/null?
Is there a more efficient way of doing this?
Code =
<?php
// DB details
$hostname = "localhost";
$username = "";
$password = "";
$dbname = "";
// Create connection
$conn = new mysqli($hostname, $username, $password, $dbname);
// Check connection
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "SELECT * FROM relevant_topics";
$result = $conn->query($sql);
if ($result->num_rows > 0) {
// Removing special characters from rows.
while($row = $result->fetch_assoc()) {
$title_clean = $row["title"];
$title_clean = strtolower($title_clean);
$title_clean = preg_replace('/\s*/ ', '', $title_clean);
$class_clean = $row["class"];
$class_clean = strtolower($class_clean);
$class_clean = preg_replace('/\s*/ ', '', $class_clean);
$related_clean_1 = $row["related1"] ;
$related_clean_1 = strtolower($related_clean_1);
$related_clean_1 = preg_replace('/[.,]\s*/ ', '', $related_clean_1);
$related_clean_2 = $row["related2"] ;
$related_clean_2 = strtolower($related_clean_2);
$related_clean_2 = preg_replace('/[.,]\s*/ ', '', $related_clean_2);
$related_clean_3 = $row["related3"] ;
$related_clean_3 = strtolower($related_clean_3);
$related_clean_3 = preg_replace('/[.,]\s*/ ', '', $related_clean_3);
$related_clean_4 = $row["related4"] ;
$related_clean_4 = strtolower($related_clean_4);
$related_clean_4 = preg_replace('/[.,]\s*/ ', '', $related_clean_4);
echo'
<div class="mix item '.$class_clean.'">
<h3>'.$row["title"].'</h3>
<p>'.$row["description"].'</p>
</br>
<p>Related Items:</p>
<p>
'.$row["related1"].'
'.$row["related2"].'
'.$row["related3"].'
'.$row["related4"].'
'.$row["related1"].',
'.$row["related2"].',
'.$row["related3"].', </p>
</br>
<div class="item-bottom '.$row["class"].'_counter">
See more
</div>
</div>
<div id="myModal'.$title_clean.'" class="modal fade">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3 class="modal-title modal-top-health">'.$row["title"].'</h3>
<br>
<p>'.$row["details"].'</p>
<br>
'.$row["linktitle_1"].',
<p>'.$row["linktitle_1_desc"].'</p>
'.$row["linktitle_2"].',
<p>'.$row["linktitle_2_desc"].'</p>
'.$row["linktitle_3"].',
<p>'.$row["linktitle_3_desc"].'</p>
</div>
</div>
</div>
</div>
';
}
} else {
echo "0 results";
}
$conn->close();
?>

Answer 1

Optimize with a loop, store the output in a variable:
// build list of titles
$titles = '';
for($i=1; $i<=7; ++$i) {
// check for data
if($row['linktitle_'.$i.'_url'] != null && $row['linktitle_'.$i] != null) {
// add to output
$titles .= '
'.$row['linktitle_'.$i].',
<p>'.$row['linktitle_'.$i.'_desc'].'</p>';
}
}
echo '
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button>
<h3 class="modal-title modal-top-health">'.$row["title"].'</h3>
<br>
<p>'.$row["details"].'</p>
<br>'.$titles.'
</div>';
You can then change that 7 to any number.
You can use htmlspecialchars() to escape the values if they might break the HTML.
$titles .= '
<a href="'.htmlspecialchars($row['linktitle_'.$i.'_url']).'">'.
htmlspecialchars($row['linktitle_'.$i]).', </a>
<p>'.htmlspecialchars($row['linktitle_'.$i.'_desc']).'</p>';
The same logic can be applied to the related links.
It could be optimized further at the database level by having a dedicated table for the titles:
table: relevant_topics_titles
topic_id | title_id | name | url | desc
Where topic_id is a foreign key to join with your table relevant_topics while title_id is a number between 1 and 7 (or less or more).
You could then fetch all the titles associated with your topic id and loop through them to build the list of titles.