如何使用reduce函数javascript对对象进行分组

Question

我已经被困在这8天了.

让我们说这是我的响应对象数组:

var items = [
{
    name: 'dell-66',
    price: 200,
    id: 12,
},
{
    name: 'hp-44',
    price: 100,
    id: 10,
},
{
    name: 'acer-33',
    price: 250,
    id: 33,
},
{
    name: 'dell-66',
    price: 200,
    id: 12,
},
{
    name: 'acer-33',
    price: 250,
    id: 33,
},
{
    name: 'dell-66',
    price: 200,
    id: 12,
},
]

到目前为止,我已设法使用reduce来累积价格.这是执行此操作的代码:

var obj = items.reduce( function (allItems, currentItem) {
var item_name = currentItem.name;
var item_price = currentItem.price;


var total_prices = allItems[item_price] = (allItems[item_price] || 0) +   
item_price;


var result = {};

result[item_name] = {
    item_price:  total_prices,
}


return Object.assign(allItems, result);
}, {} )

虽然这有效,但它不会返回我想要的结果,而是返回:

{
'100': 100,
'200': 600,
'250': 500,
'dell-66': { item_price: 600 },
'hp-44': { item_price: 100 },
'acer-33': { item_price: 500 } 
 }

这是我的意图和需要它(没有额外的键/值在顶部):

{
'dell-66': { item_price: 600 },
'hp-44': { item_price: 100 },
'acer-33': { item_price: 500 } 
 }

我怎么能这样做呢？

Answer 1

你可以这样做.

const items = [{
    name: 'dell-66',
    price: 200,
    id: 12,
  }, {
    name: 'hp-44',
    price: 100,
    id: 10,
  }, {
    name: 'acer-33',
    price: 250,
    id: 33,
  }, {
    name: 'dell-66',
    price: 200,
    id: 12,
  }, {
    name: 'acer-33',
    price: 250,
    id: 33,
  }, {
    name: 'dell-66',
    price: 200,
    id: 12,
  },
].reduce((res, obj) => {
  res[obj.name] = { 
    item_price: (obj.name in res ? res[obj.name].item_price : 0) + obj.price 
  }
  return res;
}, {})

console.log(items);

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