我按照这里的教程http://wp.smashingmagazine.com/2011/10/04/create-custom-post-meta-boxes-wordpress/
我让它按教程中的预期工作，但我不想添加类，我只想将内容添加到 footer.php 文件：
这是我在functions.php中的教程代码
/* Fire our meta box setup function on the post editor screen. */
add_action( 'load-post.php', 'smashing_post_meta_boxes_setup' );
add_action( 'load-post-new.php', 'smashing_post_meta_boxes_setup' );
/* Meta box setup function. */
function smashing_post_meta_boxes_setup() {
/* Add meta boxes on the 'add_meta_boxes' hook. */
add_action( 'add_meta_boxes', 'smashing_add_post_meta_boxes' );
/* Save post meta on the 'save_post' hook. */
add_action( 'save_post', 'smashing_save_post_class_meta', 10, 2 );
}
/* Create one or more meta boxes to be displayed on the post editor screen. */
function smashing_add_post_meta_boxes() {
add_meta_box(
'smashing-post-class', // Unique ID
esc_html__( 'Post Class', 'example' ), // Title
'smashing_post_class_meta_box', // Callback function
'post', // Admin page (or post type)
'side', // Context
'default' // Priority
);
}
/* Display the post meta box. */
function smashing_post_class_meta_box( $object, $box ) { ?>
<?php wp_nonce_field( basename( __FILE__ ), 'smashing_post_class_nonce' ); ?>
<p>
<label for="smashing-post-class"><?php _e( "Add a custom CSS class, which will be applied to WordPress' post class.", 'example' ); ?></label>
<br />
<input class="widefat" type="text" name="smashing-post-class" id="smashing-post-class" value="<?php echo esc_attr( get_post_meta( $object->ID, 'smashing_post_class', true ) ); ?>" size="30" />
</p>
<?php }
/* Save the meta box's post metadata. */
function smashing_save_post_class_meta( $post_id, $post ) {
/* Verify the nonce before proceeding. */
if ( !isset( $_POST['smashing_post_class_nonce'] ) || !wp_verify_nonce( $_POST['smashing_post_class_nonce'], basename( __FILE__ ) ) )
return $post_id;
/* Get the post type object. */
$post_type = get_post_type_object( $post->post_type );
/* Check if the current user has permission to edit the post. */
if ( !current_user_can( $post_type->cap->edit_post, $post_id ) )
return $post_id;
/* Get the posted data and sanitize it for use as an HTML class. */
$new_meta_value = ( isset( $_POST['smashing-post-class'] ) ? sanitize_html_class( $_POST['smashing-post-class'] ) : '' );
/* Get the meta key. */
$meta_key = 'smashing_post_class';
/* Get the meta value of the custom field key. */
$meta_value = get_post_meta( $post_id, $meta_key, true );
/* If a new meta value was added and there was no previous value, add it. */
if ( $new_meta_value && '' == $meta_value )
add_post_meta( $post_id, $meta_key, $new_meta_value, true );
/* If the new meta value does not match the old value, update it. */
elseif ( $new_meta_value && $new_meta_value != $meta_value )
update_post_meta( $post_id, $meta_key, $new_meta_value );
/* If there is no new meta value but an old value exists, delete it. */
elseif ( '' == $new_meta_value && $meta_value )
delete_post_meta( $post_id, $meta_key, $meta_value );
}
/* Filter the post class hook with our custom post class function. */
add_filter( 'post_class', 'smashing_post_class' );
function smashing_post_class( $classes ) {
/* Get the current post ID. */
$post_id = get_the_ID();
/* If we have a post ID, proceed. */
if ( !empty( $post_id ) ) {
/* Get the custom post class. */
$post_class = get_post_meta( $post_id, 'smashing_post_class', true );
/* If a post class was input, sanitize it and add it to the post class array. */
if ( !empty( $post_class ) )
$classes[] = sanitize_html_class( $post_class );
}
return $classes;
}
我如何将输入到字段中的数据回显到我的 footer.php 而不需要任何额外内容？
<?--php global $post; echo get_post_meta($post->ID,'smashing-post-class',true) ?>
</body>
</html>