因此,为了实现您的目标,您需要删除元框,并使用包含新值的新回调重新添加它;
so lets assume originally you have the meta-box added as below :
function adifier_custom_meta()
{
$screens = [\'page\', \'post\'];
foreach ($screens as $screen) {
add_meta_box(
\'advert_cond\', // Unique ID
esc_html__(\'Condition\', \'adifier\'), // Box title
\'adifier_get_advert_meta\', // Content callback, must be of type callable
$screen, // Post type,
\'side\'
);
}
}
add_action(\'add_meta_boxes\', \'adifier_custom_meta\');
and the original call-back output as following : function adifier_get_advert_meta($post)
{
$value = get_post_meta($post->ID, \'_advert_cond_meta_key\', true);
?>
<label for="advert_cond">Description for this field</label>
<select name="advert_cond" id="advert_cond" class="postbox">
<option value="0"><?php echo esc_html__(\'-Select-\', \'adifier\') ?></option>
<option value="1" <?php selected($value, \'1\');?>><?php echo esc_html__(\'New with tags\', \'adifier\') ?></option>
<option value="1" <?php selected($value, \'2\');?>><?php echo esc_html__(\'New with tags\', \'adifier\') ?></option>
<option value="3" <?php selected($value, \'3\');?>><?php echo esc_html__(\'Used with tags\', \'adifier\') ?></option>
<option value="4" <?php selected($value, \'4\');?>><?php echo esc_html__(\'For Parts Or Not Working\', \'adifier\') ?></option>
</select>
<?php
}
in order to change above we need to add the following functions: add_action(\'add_meta_boxes\', \'adifier_custom_meta2\');
function adifier_custom_meta2()
{
$screens = [\'page\', \'post\'];
remove_meta_box(\'advert_cond\', $screens, \'side\');
add_meta_box(
\'advert_cond\', // Unique ID
esc_html__(\'Condition\', \'adifier\'), // Box title
\'adifier_get_advert_meta2\', // Content callback, must be of type callable
$screens, // Post type,
\'side\'
);
}
and now we will add our new call-back output with our new values :
function adifier_get_advert_meta2($post)
{
$value = get_post_meta($post->ID, \'_advert_cond_meta_key\', true);
?>
<label for="advert_cond">Description for this field</label>
<select name="advert_cond" id="advert_cond" class="postbox">
<option value="0"><?php echo esc_html__(\'-Select-\', \'adifier\') ?></option>
<option value="1" <?php selected($value, \'1\');?>><?php echo esc_html__(\'New\', \'adifier\') ?></option>
<option value="2" <?php selected($value, \'3\');?>><?php echo esc_html__(\'Used\', \'adifier\') ?></option>
<option value="3" <?php selected($value, \'4\');?>><?php echo esc_html__(\'For Parts Or Not Working\', \'adifier\') ?></option>
</select>
<?php
}
有关更多信息,您可以从以下链接查看WordPress文档:
Custom Meta Boxes
Add Meta Box