Question

这是数组，如果值相等，我需要合并这些对象

var arr = [
  {item: {id: 1, name: "sample"}, amount: 1}, 
  {item: {id: 2, name: "sample"}, amount: 2}, 
  {item: {id: 1, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "newitem"}, amount: 6}, 
  {item: {id: 3, name: "newitem"}, amount: 1}
];

结果应该是这个

[
  {item: {id: 1, name: "sample"}, amount: 3}, 
  {item: {id: 2, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "newitem"}, amount: 7}
]

Answer 1

与this几乎相同。

var arr = [
  {item: {id: 1, name: "sample"}, amount: 1}, 
  {item: {id: 2, name: "sample"}, amount: 2}, 
  {item: {id: 1, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "sample"}, amount: 2}, 
  {item: {id: 3, name: "newitem"}, amount: 6}, 
  {item: {id: 3, name: "newitem"}, amount: 1}
];

var res = {};
arr.map((e) => {
  if(!res[e.item.id]) res[e.item.id] = Object.assign({},e);
  else res[e.item.id].amount += e.amount;
});
console.log(Object.values(res));

Answer 2

通过将id和name作为唯一键和Array.prototype.reduce的组合来对输入数组进行分组，并在分组对象的键上用Array.prototype.map映射结果：

var arr=[{item:{id:1,name:"sample"},amount:1},{item:{id:2,name:"sample"},amount:2},{item:{id:1,name:"sample"},amount:2},{item:{id:3,name:"sample"},amount:2},{item:{id:3,name:"newitem"},amount:6},{item:{id:3,name:"newitem"},amount:1}];

var grouppedObj = arr.reduce((all, {item: {id, name}, amount}) => {

    var key = `${id}${name}`;
    if (!all.hasOwnProperty(key)) all[key] = {item: { id, name }, amount: 0};
    all[key].amount += amount;

    return all;

}, {});

var result = Object.keys(grouppedObj).map(k => grouppedObj[k]);

console.log(result);

根据键值合并对象

2 个答案: