Loop add .last class to last item in loop

Im using wordpress and using the following to get the last 3 most recent posts:

    <?php query_posts('showposts='.$latest_num.'&cat=-'.$featured_cat.','.$latest_ignore.''); ?>
    <?php while (have_posts()) : the_post(); ?>
    <li>
        <div class="imgholder">
            <a href="/wp-content/themes/twentyten/images/slide1.jpg" data-gal="prettyPhoto[featured]" title="<?php the_title(); ?>">
                <img src="<?php echo get_post_meta($post->ID, 'thumbnail',true) ?>" width="275" height="145" alt="Post Image" class="postimg-s" />
            </a>
        </div>
        <h4><?php the_title(); ?></h4>
        <p><?php the_conten开发者_StackOverflowt('Read more...'); ?></p>
    </li>
    <?php endwhile; ?>

What I want to do is add a class named 'last' to the <li> element on the 3rd interation through the loop.

Anyone got any ideas how I could add this?

Setup a counter outside your while loop

$count = 1;

Check the modulus of that counter and output the class if required

<li <?php if(!$count % 3) echo 'class="last"; ?>>

Increment your counter before closing the loop:

    $count++;
}

Or, applied to your code:

<?php 
    $count = 1;
    while (have_posts()) : the_post(); 
?>
<li <?php if(!$count % 3) echo 'class="last"; ?>>
    <div class="imgholder">
        <a href="/wp-content/themes/twentyten/images/slide1.jpg" data-gal="prettyPhoto[featured]" title="<?php the_title(); ?>">
            <img src="<?php echo get_post_meta($post->ID, 'thumbnail',true) ?>" width="275" height="145" alt="Post Image" class="postimg-s" />
        </a>
    </div>
    <h4><?php the_title(); ?></h4>
    <p><?php the_content('Read more...'); ?></p>
</li>
<?php
    $count++; 
    endwhile; 
?>

The counter-intuitive look of the modulus condition is that whenever the counter is divisible by exactly 3 it will return 0.

Replace the line

<li>

with

<li <?php print have_posts() ? '' : ' class="last"' ?>>

The have_posts() simply calls into $wp_query->have_posts() which checks a loop counter to see if there are any posts left in the post array (source)

Li should be li

<li <?php $iCounterLi++; ($iCounterLi==3)?'class="last"':''; ?>>

Don't forgot to initialize the $iCounterLi before the loop