购物车原理

$scope.commit=function (a,a1,b,c,d,e) {
                $scope.isShow2=false;
                if(!window.localStorage){
                    alert("浏览器支持localstorage");
                    return false;
                }else{
                    var obj2 = JSON.parse(localStorage.getItem(‘aaaa‘));
                    //如果之前错过东西,那么这个obj就不为空,就直接往obj里面添加新的键值对
                    if(obj2){
                        //如果当前要存的值已经存过了,只需要加数量就行
                        if(obj2[a.product_id]){
                            obj2[a.product_id].num=b;
                            obj2[a.product_id].title=c;
                            obj2[a.product_id].img=a1;
                            obj2[a.product_id].price=d;
                            obj2[a.product_id].color=e;

                        }else{
                            a.num = 1;
                            obj2[a.product_id] = a;
                            obj2[a.product_id].num=b;
                            obj2[a.product_id].title=c;
                            obj2[a.product_id].img=a1;
                            obj2[a.product_id].price=d;
                            obj2[a.product_id].color=e;
                        }
                    }else{
                        //如果obj是空的,就证明这是第一次存值,就要新建一个obj
                        obj2 = {};
                        a.num = 1;
                        obj2[a.product_id] = a;
                    }
                    console.log(obj2);
                    localStorage.setItem(‘aaaa‘,JSON.stringify(obj2));
                }
            }