screen/application/common/model/GoodsInstall.php

<?php

namespace app\common\model;

use think\Model;

/**
 * @property float fee_fix
 */
class GoodsInstall extends Model
{
    protected $type=[
        'fee'=>'json',
    ];
    protected $autoWriteTimestamp=true;

    public function link(){
        return $this->hasMany(GoodsInstallLink::class);
    }

    public function getFee($num,$single=false){
        if($single){
            return $this->fee_fix;
        }
        return bcmul($this->fee_fix,$num);
        foreach ($this['fee'] as $fee){
            if($num>=$fee['num_min'] && $num<=$fee['num_max']){
                if($single){
                    return $fee['amount'];
                }
                return bcmul($fee['amount'],$num);
            }
       }
        return 0;
    }






























    public static function init()
    {
        self::afterDelete(function (self $goodsInstall){
            $goodsInstall->link()->delete();
        });
    }
}