<?php
/**
 * 广告
 * @author wesmielr
 */
namespace app\index\service;
use think\Db;
class AdvertService
{
    /**
     * 获取对应位置轮播列表
     * @param $slideId 广告位ID
     * @param int $num 获取数量
     * @param string $field 字段
     * @return array
     * @throws \think\db\exception\DataNotFoundException
     * @throws \think\db\exception\ModelNotFoundException
     * @throws \think\exception\DbException
     */
    public static function getListBySlide($slideId, $num=6, $field=''){
        $field = $field? $field : 'id,title,image,url,target';
        return Db::name('slide_item')->where(['status'=> 1])
            ->where(function($query) use ($slideId){
                if(is_array($slideId)){
                    $query->whereIn('slide_id', $slideId);
                }else{
                    $query->where('slide_id', $slideId);
                }
            })
            ->field($field)
            ->order('list_order')
            ->limit($num)
            ->select()
            ->toArray();
    }

}