一、样例

二、需求

调用goods.js这个单例完成对goods数据的增删查改

class Goods {constructor() {const data = localStorage.getItem("qf-goods-data");this.goods = data ? JSON.parse(data) : [];}time = 500;/*** 获取商品* @returns*/getGoods() {return new Promise((resolve, reject) => {setTimeout(() => {resolve(this.goods);}, this.time);});}/*** 创建商品* @param {} params* @returns*/createGoods(params) {return new Promise((resolve, reject) => {setTimeout(() => {if (!params) {reject("不能不传");return;}console.log(params, this.goods);this.goods = [...this.goods, { ...params }];resolve("成功");this.keepData();}, this.time);});}/*** 传一个列表的下表* @param {*} index* @returns*/delGoods(index) {return new Promise((resolve, reject) => {if (typeof index !== "number") {reject("必须传数值");}const goods = [...this.goods];goods.splice(index, 1);this.goods = goods;resolve();this.keepData();});}/*** 传一个下标 在传一个数据* @param {*} index* @param {*} data* @returns*/updateGoods(index, data) {return new Promise((resolve, reject) => {if (typeof index !== "number") {reject("必须传数值");}const goods = [...this.goods];goods[index] = data;this.goods = [...goods];resolve();this.keepData();});}/*** 根据下标获取最新的数据* @param {*} index* @returns*/getGoodsDetail(index) {return new Promise((resolve, reject) => {if (typeof index !== "number") {reject("必须传数值");}resolve(this.goods[index]);});}async keepData() {const data = await this.getGoods();localStorage.setItem("qf-goods-data", JSON.stringify(data));}
}export default new Goods();

整个操作所有的逻辑放到redux中，页面只负责view层的渲染

ta", JSON.stringify(data));
}
}

export default new Goods();

### 整个操作所有的逻辑放到redux中，页面只负责view层的渲染### 按照页面上出现的功能完成代码