Functions PHP

/* Adds Schema Event Posts to Gardening Classes Page */
function wpb_postsbycategory() {
/* the query */
$the_query = new WP_Query( array( 'post_type' => 'schema_event_post', 'posts_per_page' => 8 ) );

/* The Loop */
if ( $the_query->have_posts() ) {
	$string .= '<ul class="postsbycategory widget_recent_entries">';
	while ( $the_query->have_posts() ) {
		$the_query->the_post();
			if ( has_post_thumbnail() ) {
			$string .= '<li>';
			$string .= '<a href="' . get_the_permalink() .'" rel="bookmark">' . get_the_post_thumbnail($post_id, array( 150, 150) ) . get_the_title() .'</a><br /> '. get_the_excerpt() .'</li><br />';
			} else {
			/* if no featured image is found */
			$string .= '<li><a href="' . get_the_permalink() .'" rel="bookmark">' . get_the_title() .'</a><br /> '. get_the_excerpt() .'</li><br />';
			}
			}
	} else {
	/* no posts found */
}
$string .= '</ul>';

return $string;

/* Restore original Post Data */
wp_reset_postdata();
}
/* Add a shortcode */
add_shortcode('categoryposts', 'wpb_postsbycategory');

/* Enable shortcodes in text widgets */
add_filter('widget_text', 'do_shortcode');