wordpress调用自定义字段值

<?php $key="字段名"; echo get_post_meta($post->ID, $key, true); ?>

'.get_field('字段名').'

get_post_meta($post->ID, "quan", $single = true)

echo '<h2><a'._post_target_blank().' href="'.get_permalink().'" rel="external nofollow"  title="'.get_the_title()._get_delimiter().get_bloginfo('name').'">'.get_the_title().'',''.get_field('red_title').'</a></h2>';

$quan= get_post_meta($post->ID, "自定义字段", $single = true);
if($quan){
echo '<div class="quanquan">领取'.$quan.'优惠券</div>';
}
else echo '';