Codex

Function Reference/add meta box

Contents

Description

The add_meta_box() function was introduced in WordPress 2.5. It allows plugin developers to add sections to the Write Post, Write Page, and Write Link editing pages.

Usage

 <?php add_meta_box( $id, $title, $callback, $page, $context, $priority ); ?> 

Parameters

$id 
(string) HTML 'id' attribute of the edit screen section
$title 
(string) Title of the edit screen section, visible to user
$callback 
(string) Function that prints out the HTML for the edit screen section.
$page 
(string) The type of Write screen on which to show the edit screen section ('post', 'page', or 'link')
$context 
(string) The part of the page where the edit screen section should be shown ('normal', 'advanced' or (since 2.7) 'side')
$priority 
(string) The priority within the context where the boxes should show ('high' or 'low')

Example

Here is an example that adds a custom section to the post and page editing screens. It will will work with WordPress 2.5 and also with earlier versions of WordPress (when the add_meta_box function did not exist). 

<?php
/* Use the admin_menu action to define the custom boxes */
add_action('admin_menu', 'myplugin_add_custom_box');

/* Use the save_post action to do something with the data entered */
add_action('save_post', 'myplugin_save_postdata');

/* Adds a custom section to the "advanced" Post and Page edit screens */
function myplugin_add_custom_box() {

  if( function_exists( 'add_meta_box' )) {
    add_meta_box( 'myplugin_sectionid', __( 'My Post Section Title', 'myplugin_textdomain' ), 
                'myplugin_inner_custom_box', 'post', 'advanced' );
    add_meta_box( 'myplugin_sectionid', __( 'My Post Section Title', 'myplugin_textdomain' ), 
                'myplugin_inner_custom_box', 'page', 'advanced' );
   } else {
    add_action('dbx_post_advanced', 'myplugin_old_custom_box' );
    add_action('dbx_page_advanced', 'myplugin_old_custom_box' );
  }
}
   
/* Prints the inner fields for the custom post/page section */
function myplugin_inner_custom_box() {

  // Use nonce for verification

  echo '<input type="hidden" name="myplugin_noncename" id="myplugin_noncename" value="' . 
    wp_create_nonce( plugin_basename(__FILE__) ) . '" />';

  // The actual fields for data entry

  echo '<label for="myplugin_new_field">' . __("Description for this field", 'myplugin_textdomain' ) . '</label> ';
  echo '<input type="text" name="myplugin_new_field" value="whatever" size="25" />';
}

/* Prints the edit form for pre-WordPress 2.5 post/page */
function myplugin_old_custom_box() {

  echo '<div class="dbx-b-ox-wrapper">' . "\n";
  echo '<fieldset id="myplugin_fieldsetid" class="dbx-box">' . "\n";
  echo '<div class="dbx-h-andle-wrapper"><h3 class="dbx-handle">' . 
        __( 'My Post Section Title', 'myplugin_textdomain' ) . "</h3></div>";   
   
  echo '<div class="dbx-c-ontent-wrapper"><div class="dbx-content">';

  // output editing form

  myplugin_inner_custom_box();

  // end wrapper

  echo "</div></div></fieldset></div>\n";
}

/* When the post is saved, saves our custom data */
function myplugin_save_postdata( $post_id ) {

  // verify this came from the our screen and with proper authorization,
  // because save_post can be triggered at other times

  if ( !wp_verify_nonce( $_POST['myplugin_noncename'], plugin_basename(__FILE__) )) {
    return $post_id;
  }

  if ( 'page' == $_POST['post_type'] ) {
    if ( !current_user_can( 'edit_page', $post_id ))
      return $post_id;
  } else {
    if ( !current_user_can( 'edit_post', $post_id ))
      return $post_id;
  }

  // OK, we're authenticated: we need to find and save the data

  $mydata = $_POST['myplugin_new_field'];

  // TODO: Do something with $mydata 
  // probably using add_post_meta(), update_post_meta(), or 
  // a custom table (see Further Reading section below)

   return $mydata;
}
?>

Further Reading

External Resources

See also index of Function Reference and index of Template Tags.
Retrieved from "http://codex.wordpress.org/Function_Reference/add_meta_box"

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