I have a wordpress function that displays adverts every so often. When are not shown essentially I would prefer to the div to display:none;
I can not seem to figure out the correct PHP function in order for the div not to display when a advert is uploaded.
<div class="advert" <?php if(!empty($_GET['details'])) {echo "style='display: none'";} ?>></div>
Why not completely not echo "advert" element?
if ( !empty($_GET['details']) ){
echo '<div class="advert">add text</div>';
}
if you really want to just hide, you can assign hide class
<div class="advert <?php echo ( empty($_GET['details'])? 'hide' : '' );">add text</div>
then you would need to add "hide" class with display:none in your style.css
Above is shorthand/ternary if/else statement used, its great if you need output some string.
And, please don't output/trust any user input i.e. $_GET['details'] 'as is' anywhere without escaping it, for security reasons.
Wordpress have plenty easy-to-use escape functions, like esc_attr() and esc_html().
This should do it for you
<?php
$advert_display_string = "";
if (!isset($_GET['details'])) {
$advert_display_string = "style='display: none'";
}
?>
<div class="advert" <?php echo $advert_display_string ; ?> ></div>`
but having said that, instead of displaying it and then hiding it with css, you could just choose only to display it if you need it there, like below
<?php
if (isset($_GET['details'])) {
?>
<div class="advert"></div>
<?
}
?>
<div class="advert" <?php if(empty($_GET['details'])) {echo "style='display: none'";} ?>></div>?