WordPress 调用同分类或指定某分类下的随机文章

<?php
    $cat = get_the_category();
    foreach($cat as $key=>$category){
		$cat_id = $category->term_id;
    }
    $args = array('orderby' => 'rand','showposts' => 10,'cat' => $$cat_id );
    $query_posts = new WP_Query();
    $query_posts->query($args);
    while ($query_posts->have_posts()) : $query_posts->the_post();
?>
    <li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
<?php endwhile;?>

<?php 
	query_posts('showposts=10&cat=1&orderby=rand');
	while(have_posts()) : the_post();
?>
<a href="<?php the_permalink(); ?>" title="<?php the_title(); ?>"><?php the_title(); ?></a>
<?php endwhile; ?>