Check if a variable is empty

Question

I have some user-submitted variables that I want to display in a different part of my site like this:

Term: 


        
                      

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Answer 1

If isset() does not work, try empty() instead:

<?php if( !empty( $key ) ): ?> 
    <div class="pre_box">Term: </div>
    <div class="entry">
         <?php echo get_post_meta($post->ID, $key, true); ?>
    </div> 
<?php endif; ?>

isset() will deliver TRUE if the value is set and has a value different from NULL.

empty() instead will deliver TRUE (hence !empty() results in FALSE) for:

• "" (an empty string)
• 0 (0 as an integer)
• "0" (0 as a string)
• NULL
• FALSE
• array() (an empty array)
• var $var; (a variable declared, but without a value in a class)

I assume your $key is set but with an empty string. Thus, empty() is the way to go here.

Answer 2

<?php if( isset( $var ) ): ?><p><?php echo $var ?></p><?php endif; ?>

If $var is set it will display the paragraph with $var, otherwise nothing will be displayed

Answer 3

<?php 
    $post_meta = get_post_meta($post->ID, 'term', true);
    if (!empty($post_meta)) {
?>
        <div class="pre_box">Term: </div>
        <div class="entry"><?php echo $post_meta; ?></div>
<?php
    }
?>

Answer 4

Well they way your code is above, $key will never be empty, thus the pre_box will always be displayed. You're setting $key = 'term', which gives it a value so !empty($key) or isset($key) will always be true.

Casey's solution should give you the result you're going for.