计算每个类别的所有特殊自定义字段（Wordpress）

With this script my special custom field "Nickname" is counted only once, also if these field is available twice or more in a post.

Is there a way to count all special custom fields called "Nickname" in a post?

Thats the script:

<?php
$posts_with_nickname = get_posts(array(
        'category__in' => array(2,5),
        'meta_key' => 'Nickname',
        'showposts' => -1,
));

printf('I have %d posts with "Nickname"!', count($posts_with_nickname));
?>

You may want to use meta_query

<?php
$posts_with_nickname = get_posts(
    'category__in' => array(2,5),
    'meta_query'   => array(
        array(
            'key'     => 'Nickname',
            'value'   => '',
            'compare' => 'NOT LIKE',
        ),
    ),
    'showposts'    => -1,
);

printf('I have %d posts with "Nickname"!', count($posts_with_nickname));