纵横比的基本检查。显示为横向、方形或纵向

if ( !has_post_thumbnail()) { 
    return \'Error\'; 
} else {
    $image = wp_get_attachment_image_src( get_post_thumbnail_id($post->ID), \'\');
    $image_w = $image[1];
    $image_h = $image[2];

    if ($image_w > $image_h) { 
        echo \'landscape\';
    }
    elseif ($image_w == $image_h) { 
        echo \'square\';
    }
    else { 
        echo \'portrait\';
    } 
}