1、在 functions.php
文件增加:
function catch_that_image() {
global $post, $posts;
$first_img = '';
ob_start();
ob_end_clean();
$output = preg_match_all('/<img.+src=[\'"]([^\'"]+)[\'"].*>/i', $post->post_content, $matches);
$first_img = $matches[1][0];
if(empty($first_img)) {
$first_img = "/path/to/default.png";
}
return $first_img;
}
2、模板文件调用:
if ( get_the_post_thumbnail($post_id) != '' ) {
echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
the_post_thumbnail();
echo '</a>';
} else {
echo '<a href="'; the_permalink(); echo '" class="thumbnail-wrapper">';
echo '<img src="';
echo catch_that_image();
echo '" alt="" />';
echo '</a>';
}