商品添加购物车，传递参数到页面，页面跳转到购物车页面

public function addCart()
{
   //1. 检测如果是get请求 在执行浏览器刷新，则跳回首页
   if(request()->isGet()){
      $this->redirect('index/index');
   }
$params = input();
$validateRes = $this->validate($params,[
          'goods_id'=>'require|gt:0',
          'spec_goods_id'=>'require|gt:0',
          'number'=>'require|gt:0',
       ]);
if($validateRes !== true){
      $this->error('信息错误');
  }
//4. 调用加入购物车逻辑层功能
   CartLogic::addCart($params['goods_id'],$params['spec_goods_id'],$params['number']);
$goods=Goods::getGoodsWithSpec($params['spec_goods_id'],$params['goods_id']);
return view('cart/success-cart',['goods'=>$goods,'number'=>$params['number']]);
}

前面调用addCart如果登录商品存入购物车表，没登录商品存入cookie
static public function addCart($goods_id,$spec_goods_id,$number,$is_selected=1)
{
   //1. 判断 已登录-商品信息添加到数据表中   未登录-商品信息添加到cookie中
   if(session('?info')){
        $user_id=session('info');
      //1.1 已登录- 组装数据，用于查询是否存在相同的商品信息
      $goodsData = [
         'user_id' => $user_id,
         'goods_id' => $goods_id,
         'spec_goods_id' => $spec_goods_id,
      ];
 //1.2 查询此信息在购物车表中是否存在
      $info = Cart::where($goodsData)->find();
      //1.3 判断是否存在同商品
      if($info){
         //叠加数量
         $info->number += $number;
         $info->is_selected = $is_selected;
         $info->save();
}else{
//添加数量
         $goodsData['number'] = $number;
         $goodsData['is_selected'] = $is_selected;
         Cart::create($goodsData,true);
}
return '已登录，添加数据到表中';
}else{
//2.1 未登录,先从cookie中取出原始数据
      $cartInfo = cookie('cart') ?: [];
//2.2 拼接商品ID和sku id的下标组合 类似于 61_804 目的是为了查询此商品是否已经存在 存在叠加数量 不存在正常添加
      $key = $goods_id.'_'.$spec_goods_id;
//2.3 判断是否存在商品
      if(isset($cartInfo[$key])){
//叠加数量
         $cartInfo[$key]['number'] += $number;
            $data[$key]['is_selected'] = $is_selected;
      }else{
//正常添加
     $cartInfo[$key] = [
            'id' => $key,
            'user_id' => '',
            'goods_id' => $goods_id,
            'spec_goods_id' => $spec_goods_id,
            'number' => $number,
                'is_selected'=>$is_selected,
         ];
}
//2.4 将处理好的数组内容添加到cookie中
      cookie('cart',$cartInfo,86400);
      return $key.'暂未登录，添加数据到cookie中';
}
}

页面展示，进入购物车详情

    

        
商品已成功加入购物车！
        

            

                

                

                    
{$goods.goods_name}
                    
{$goods.value_names} 数量: {$number}
                
            
            

                查看商品详情
                去购物车结算 > 
            
        

购物车页面展示方法 
public function index()
    {
        //1. 调用逻辑层查询购物车数据方法(结果为各种ID)
        $data = CartLogic::getAllCart();
        //2. 循环查询所有数据
        foreach ($data as &$v) {
           $v['goods']=Goods::getGoodsWithSpec($v['spec_goods_id'],$v['goods_id'])->toArray();
        }
        unset($v);
return view('cart/cart',compact('data'));
    }

调用查询购物车数据方法

static public function getAllCart()
{
    //1. 判断是否登录  登录-查数据表  未登录-查cookie
    if(session('?info')){
//登陆-查数据表
        $uid = session('info');
//查询购物车表中数据
        $data = Cart::field('id,user_id,goods_id,spec_goods_id,number')
            ->where('user_id',$uid)->select();
        $data = (new \think\Collection($data))->toArray();
    }else{
//未登陆-取cookie值
        $data = cookie('cart') ?: [];
        //将结果转化为数组格式
        $data = array_values($data);
    }
return $data;
}

调用商品表数据

static public function getGoodsWithSpec($spec_goods_id,$goods_id)
{   
    //判断此商品是否存在sku
    if($spec_goods_id){
        //有sku信息
        $where = ['t2.id' => $spec_goods_id];
    }else{
        //无sku信息
        $where = ['t1.id' => $goods_id];
    }
    //查询一条记录
    $data = self::alias('t1')    //t1 == goods
                ->join('pyg_spec_goods t2','t1.id = t2.goods_id','left')    //t2 == pyg_spec_goods
                ->field('t1.*,t2.value_ids,t2.value_names,t2.price,t2.cost_price as cost_price2,t2.store_count')
                ->where($where)
                ->find();
    //如果存在sku的价格 则替换到原价格上 
    if($data['price'] > 0){
        $data['goods_price'] = $data['price'];
    }
    if($data['cost_price2']>0){
        $data['cost_price'] = $data['cost_price2'];
    }
    return $data;
}