Node JS：基于城市的JSON重构

Question

我有以下 JSON 对象：

    const data = [
    {
        "city name": "Chennai",
        "product name": "Apple",
        "no of qty": 2,
        "indvidual price": 50,
        "gst tax": 0.18
    },
    {
        "city name": "Chennai",
        "product name": "Samsung",
        "no of qty": 1,
        "indvidual price": 150,
        "gst tax": 0.18
    },
    {
        "city name": "Delhi",
        "product name ": "MIUI",
        "no of qty": 5,
        "indvidual price": 100,
        "gst tax": 0.18
    },
    {
        "city name": "Chennai",
        "product name": "Redmi",
        "indvidual price": 100,
        "no of qty": 1,
        "gst tax": 0.18
    },
    {
        "city name": "Delhi",
        "product name": "Realme",
        "indvidual price": 100,
        "no of qty": 5,
        "gst tax": 0.18
    },
];

我正在尝试根据城市和计算总体数量和成本进行分组。基于单个产品的总成本有不同的 GST，我们需要计算并添加到总价值中。

例外的JSON是这样的，

var result = [
    {
        "city": "chennai",
        "totalqty": 4, //Total qty based on the city
        "totalPrice": 354 //With the GST, Each product have separate gst(59+177+118)
    },
    {
        "city": "Delhi",
        "totalqty": 10, //Total qty based on the city
        "totalPrice": 236 //With the GST, Each product have separate gst(118+118)
    }
]

Answer 1

您可以使用reduce轻松实现此结果

const data = [{
    "city name": "Chennai",
    "product name": "Apple",
    "no of qty": 2,
    "indvidual price": 50,
    "gst tax": 0.18,
  },
  {
    "city name": "Chennai",
    "product name": "Samsung",
    "no of qty": 1,
    "indvidual price": 150,
    "gst tax": 0.18,
  },
  {
    "city name": "Delhi",
    "product name ": "MIUI",
    "no of qty": 5,
    "indvidual price": 100,
    "gst tax": 0.18,
  },
  {
    "city name": "Chennai",
    "product name": "Redmi",
    "indvidual price": 100,
    "no of qty": 1,
    "gst tax": 0.18,
  },
  {
    "city name": "Delhi",
    "product name": "Realme",
    "indvidual price": 100,
    "no of qty": 5,
    "gst tax": 0.18,
  },
];

const dict = {
  city: "city name",
  qty: "no of qty",
  Price: "indvidual price",
  gst: "gst tax",
};

const result = data.reduce((acc, curr) => {
  const cityAlredyExist = acc.find((o) => o.city === curr[dict.city]);
  if (cityAlredyExist) {
    cityAlredyExist.totalqty += curr[dict.qty];
    cityAlredyExist.totalPrice +=
      curr[dict.Price] + curr[dict.Price] * curr[dict.gst];
  } else {
    acc.push({
      city: curr[dict.city],
      totalqty: curr[dict.qty],
      totalPrice: curr[dict.Price] + curr[dict.Price] * curr[dict.gst],
    });
  }
  return acc;
}, []);

console.log(result);

/* This is not a part of answer. It is just to give the output fill height. So IGNORE IT */

.as-console-wrapper {
  max-height: 100% !important;
  top: 0;
}

Answer 2

reduce 在这种情况下很有用。然后，您可以使用Object.values 拉出与您的输出对应的新数组。

如果您的 JSON 中有带空格的键，只需替换

const { gst, price, qty } = rest;

与

const { 'gst tax': gst, 'individual price': price, qty } = rest;

这会分配一个与其余代码中的变量匹配的标签，因此您无需更改任何其他内容。

const data=[{city:"Chennai",product:"Apple",qty:2,price:50,gst:.18},{city:"Chennai",product:"Samsung",qty:1,price:150,gst:.18},{city:"Delhi",product:"MIUI",qty:5,price:100,gst:.18},{city:"Chennai",product:"Redmi",price:100,qty:1,gst:.18},{city:"Delhi",product:"Realme",price:100,qty:5,gst:.18}];

const out = data.reduce((acc, c, i, arr) => {

  // Destructure the city and product, and use `rest`
  // to destructure the rest
  const { city, product, ...rest } = c;
  const { gst, price, qty } = rest;

  // If the city doesn't exist on the object, create it
  // and set some default values
  acc[city] = (acc[city] || { city, product, qty: 0, price: 0 });

  // Update the quantity, and price
  acc[city].qty += qty;
  acc[city].price += gst * price + price;

  // Return the object for the next iteration
  return acc;
}, {});

// And then grab the Object.values
console.log(Object.values(out));