$key = "key";
$meta_boxes = array(
    "item-count" => array(
    "name" => "item-count",
    "type" => "itemcount",
    "std" => "",
    "title" => "How many items?",
    "description" => "Choose item count",
    "options" => array(
        "0" => "None", "1" => "1", "2" => "2", "2" => "2", "3" => "3", "4" => "4"),
    ),
    "item-color" => array(
    "name" => "item-color",
    "type" => "itemcolor",
    "std" => "",
    "title" => "Item Colors",
    "description" => "Choose item colors",
    "options" => array(
        "black" => "Black", "white" => "White", "red" => "Red"),
    ),
);

function create_meta_box() {
global $key;

  if ( function_exists(\'add_meta_box\') ) {
      add_meta_box( \'item-div\', \'Item Infos\', \'display_meta_box\', \'post\', \'normal\', \'high\' );
  }
}
function display_meta_box() {
    global $post, $meta_boxes, $key;

    wp_nonce_field( plugin_basename( __FILE__ ), $key . \'_wpnonce\', false, true );

    foreach($meta_boxes as $meta_box) {
    $data = get_post_meta($post->ID, $key, true);

    switch ( $meta_box[\'type\'] ) {

    case "itemcount":
    echo \'<table style="margin-bottom: 20px;" class="widefat">\';
    echo \'<thead><tr><th>\'.$meta_box[\'title\'].\'</th></tr></thead>\';
    echo \'<tbody style="background:#f9f9f9;"><tr><td>\';
    echo\'<select name="\'.$meta_box[\'name\'].\'[]" multiple size="3">\';
    function new_in_array( $needle, $haystack )  { if (is_array($haystack)) { return in_array($needle, $haystack); } else { return false; } }
$getcountmeta = get_post_meta( $post->ID, \'key\', true );
$getcountmeta2 = $getcountmeta[\'item-count\']; ?>
<?php foreach ($meta_box[\'options\'] as $item_count_key => $item_count_option) { ?>
<option <?php if ( new_in_array($item_count_key,$getcountmeta2)) { ?> selected <?php } ?> value="<?php echo $item_count_key; ?>"><?php echo $item_count_option; ?></option>
<?php }
    echo \'</select>\';
    echo \'<p>\'.$meta_box[\'description\'].\'</p>\';
    echo \'</td></tr></tbody></table></div>\';
    break;

    case "itemcolor":
    echo \'<table style="margin-bottom: 20px;" class="widefat">\';
    echo \'<thead><tr><th>\'.$meta_box[\'title\'].\'</th></tr></thead>\';
    echo \'<tbody style="background:#f9f9f9;"><tr><td>\';
    echo\'<select name="\'.$meta_box[\'name\'].\'[]" multiple size="3">\';
    function new_in_array2( $needle, $haystack )  { if (is_array($haystack)) { return in_array($needle, $haystack); } else { return false; } }
$getcolormeta = get_post_meta( $post->ID, \'key\', true );
$getcolormeta2 = $getcolormeta[\'item-color\']; ?>
<?php foreach ($meta_box[\'options\'] as $item_color_key => $item_color_option) { ?>
<option <?php if ( new_in_array2($item_color_key,$getcolormeta2)) { ?> selected <?php } ?> value="<?php echo $item_color_key; ?>"><?php echo $item_color_option; ?></option>
<?php }
    echo \'</select>\';
    echo \'<p>\'.$meta_box[\'description\'].\'</p>\';
    echo \'</td></tr></tbody></table></div>\';
    break;
    }
    }
}

function save_meta_box( $post_id ) {
global $post, $meta_boxes, $key;

foreach($meta_boxes as $meta_box) {
$data[ $meta_box[ \'name\' ] ] = $_POST[ $meta_box[ \'name\' ] ];

}

if ( !wp_verify_nonce( $_POST[ $key . \'_wpnonce\' ], plugin_basename(__FILE__) ) )
return $post_id;

if ( !current_user_can( \'edit_post\', $post_id ))
return $post_id;

update_post_meta( $post_id, $key, $data );
}

我在上面粘贴的代码将“key”meta\\u键添加到数据库中，其meta\\u值为

a:2:{s:10:"item-count";a:2:{i:0;s:1:"1";i:1;s:1:"2";}s:10:"item-color";a:2:{i:0;s:5:"black";i:1;s:5:"white";}} //i chose counts 1 and 2, colors black and white

我想要实现的是，将这些值存储在单独的元键中，而不是唯一的“key”meta\\u键，例如

meta_key     item_color
meta_value   a:2:{i:0;s:5:"black";i:1;s:5:"white";}

我不知道怎么做。有什么建议吗？

$key = "key";

update_post_meta( $post_id, $key, $data );

$key = "item_color";