Using if for non-blank data

I have text field in a database that will either be blank (Null) depending upon if the user completes a text area in form.

I'd like to show a link based on that field only if the field has data in it. I had thought this would work, but its not:

<?php if($custom_rules != " "){ ?>
html to custom link here
<? } ?>

Use if (empty($var)) or (if $var > '')

you can use

<?php
if($var){
// $var is NOT empty
} else {
// $var is empty
}
?>

But I like the empty function better

you can use

<?php
if($var){
// $var is NOT empty
} else {
// $var is empty
}
?>

But I like the empty function better

That so does not work.

really? I've tested it in few script and when the var is empty, it is like the var = false, no?