JavaScript、TypeScript 实现通过某个属性值对「对象数组」进行

背景

Antd 表格批量处理获取数据相关逻辑

在实际项目业务逻辑开发中，前端调用接口请求数据，后台返回的列表数据格式一般是没按某一控制条件进行分组，这时候为了实现某些业务需求，就需要我们自己对数据重新进行处理，从而获得我们想要的数据结构。

比如我想获得候选的内容中每个类别是多少数量

下面就是通过某个属性值对「对象数组」进行分组生成「结果对象数组」，一个分类的过程。

效果

const list = [{id: 1,name: "杨一",position: "前端"},{id: 2,name: "杨二",position: "前端"},{id: 3,name: "杨三",position: "前端"},{id: 4,name: "杨四",position: "后端"},{id: 5,name: "杨五",position: "后端"}, {id: 6,name: "杨六",position: "算法"}，{id: 7,name: "杨七",position: "算法"}，{id: 8,name: "杨八",position: "算法"}，]countSelectedMember(list)

变成

踩坑 方法一

  const countSelectedMember = (array: any[]): any[] => {const classifiedMember: any[] = [];for (let i = 0; i < array.length; i++) {if (array[i].position === null) continue;//注意脏数据else if (classifiedMember.length == 0) {classifiedMember.push({position: array[i].position,data: [array[i]],});} else {let index: number = classifiedMember.findIndex((item) => item.position == array[i].position,);if (index >= 0) {classifiedMember[index].data.push(array[i]);} else {classifiedMember.push({position: array[i].position,data: [array[i]],});}}}return classifiedMember;};

方法二

  const countSelectedMember = (selectedMember: any[]): Map<string, number> => {let mapPosition: Map<string, number> = new Map();for (const member of selectedMember) {if (member.position === null) {if (mapPosition.has('职位类别缺失')) {const curNo: number = mapPosition.get('职位类别缺失');mapPosition.set('职位类别缺失', curNo + 1);} else {mapPosition.set('职位类别缺失', 1);}} else if (!mapPosition.has(member.position[0])) {mapPosition.set(member.position[0], 1);} else {const cur: any | undefined = mapPosition.get(member.position[0]);mapPosition.set(member.position[0], cur + 1);}}return mapPosition;};// 后续渲染let memberPosition: Map<string, number> = countSelectedMember(selectedRows);let ul: any[] = [];memberPosition.forEach((value, key) =>ul.push(<li>{`${key}:${value}名`}</li>));