找到lib_goods.php第147行，代码
$sql = 'SELECT g.goods_id, g.goods_name, g.shop_price,g.goods_thumb, SUM(og.goods_number) as goods_number ' .
1.替换一下代码
$sql = 'SELECT g.goods_id, g.goods_name, g.shop_price,g.promote_price,g.goods_thumb, SUM(og.goods_number) as goods_number ' .
2.第171行，$arr[$i]['price'] = price_format($arr[$i]['shop_price']); 替换为以下代码
if($arr[$i]['promote_price'] !='0.00'){
$arr[$i]['price'] = price_format($arr[$i]['promote_price']);
}else{
$arr[$i]['price'] = price_format($arr[$i]['shop_price']);
}