是否有与图像关联的自定义元字段？如果是这样，请将其放在您的函数中。php：

<?php
$trim_length = 21;  //desired length of text to display
$custom_field = \'your custom field key here\';
$value = get_post_meta($post->ID, $custom_field, true);
if ($value) {
  echo \'<p>I want to use: \' . rtrim(substr($value,0,$trim_length)) . \'...</p>\';
}
?>

希望这有助于干杯。