重构 Javascript 对象遍历

Question

我的代码确实产生了所需的输出。但是，在我看来，使用这些嵌套的 for 循环有点难看，我正在尝试重构我的工作。

我的问题是：关于重构代码以避免使用这些嵌套 for 循环，您有什么建议吗？

我想遍历嵌套对象并以所有唯一键的结果以及该唯一键的所有值的数组结束。

{"ABC":["1","100","6"],"DEF":["10","2","5"],"GHI":["14","9"],"HGI":["4"]}

const data = {
  something: [
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "1"
          },
          {
            title: "DEF",
            amount: "10"
          },
          {
            title: "GHI",
            amount: "14"
          }
        ],
      }
    },
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "100"
          },
          {
            title: "DEF",
            amount: "2"
          },
          {
            title: "GHI",
            amount: "9"
          }
        ],
      }
    },
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "6"
          },
          {
            title: "DEF",
            amount: "5"
          },
          {
            title: "HGI",
            amount: "4"
          }
        ],
      }
    }
  ]
};


const results = {};
data.something.forEach((item) => {
  item.innerSomething.list.forEach((list) => {
    if (results[list.title]) {
      // exists already, just push the amount
      results[list.title].push(list.amount)
    } else {
      // Is unique so far, add it to the object
      results[list.title] = [list.amount];
   }
  })
});

console.log(`results: ${JSON.stringify(results)}`);
// These results are the correct and desired output
// {"ABC":["1","100","6"],"DEF":["10","2","5"],"GHI":["14","9"],"HGI":["4"]}

Answer 1

对于它的价值，这是我的写法。

const data = {
  something: [
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "1"
          },
          {
            title: "DEF",
            amount: "10"
          },
          {
            title: "GHI",
            amount: "14"
          }
        ],
      }
    },
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "100"
          },
          {
            title: "DEF",
            amount: "2"
          },
          {
            title: "GHI",
            amount: "9"
          }
        ],
      }
    },
    {
      innerSomething: {
        list: [
          {
            title: "ABC",
            amount: "6"
          },
          {
            title: "DEF",
            amount: "5"
          },
          {
            title: "GHI",
            amount: "4"
          }
        ],
      }
    }
  ]
};

const results = {};
for (let something of data.something) {
  for (let item of something.innerSomething.list) {
    const { title, amount } = item;
    results[title] = results[title] || [];
    results[title].push(amount);
  }
}

console.log(`results: ${JSON.stringify(results)}`);

Answer 2

你的实现没问题，tbh。考虑到您的输入对象的结构众所周知：

data.something.forEach(({ innerSomething: { list } }) =>
  list.forEach(({ title, amount }) => 
    results[title] = [...results[title] || [], amount]))

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