如何從對象數組中的嵌套數組中獲取數組值的組合

Question

我有一個具有以下結構的對象數組：

 var varientSections = [
  {
    type: "frame",
    values: ["black", "white", "wood"]
  },
  {
    type: "finish",
    values: ["matte", "glossy"]
  }
];

我想得到數組值的組合並用它創建一個新列表。 現在，我可以使用名為getCombination（varientSections）的方法從嵌套數組值中檢索組合。 但是，我不知道如何使用以下結構創建新列表：

var results = [
  {
    attributes: [
      {
        type: "frame",
        value: "black"
      },
      {
        type: "finish",
        value: "matte"
      }
    ]
  },
  {
    attributes: [
      {
        type: "frame",
        value: "black"
      },
      {
        type: "finish",
        value: "glossy"
      }
    ]
  },
  {
    attributes: [
      {
        type: "frame",
        value: "white"
      },
      {
        type: "finish",
        value: "matte"
      }
    ]
  },
  {
    attributes: [
      {
        type: "frame",
        value: "white"
      },
      {
        type: "finish",
        value: "glossy"
      }
    ]
  },
  {
    attributes: [
      {
        type: "frame",
        value: "wood"
      },
      {
        type: "finish",
        value: "matte"
      }
    ]
  },
  {
    attributes: [
      {
        type: "frame",
        value: "wood"
      },
      {
        type: "finish",
        value: "glossy"
      }
    ]
  }
];

以下是我的代碼：

function getCombinations(arr) {
  if (arr.length === 0) {
    return [[]];
  }

  let [current, ...rest] = arr;
  let combinations = getCombinations(rest);

  var result = current.values.reduce(
    (accumulator, currentValue) => [
      ...accumulator,
      ...combinations.map(c => [currentValue, ...c])
    ],
    []
  );
  console.log("result is ");
  console.log(result);
  return result;
}

let varientCombinations = getCombinations(varientSections);
console.log(varientCombinations);

let updatedVarientDetails = [];
varientSections.forEach((varientSection, index) => {
  let type = varientSection.type;
  varientCombinations.forEach(combination => {
    let obj = [
      {
        type: type,
        value: combination[index]
      },
    ];
    updatedVarientDetails.push(obj);
  });
});

console.log(updatedVarientDetails);

Answer 1

你可以得到笛卡爾積，然后給它想要的風格。 名稱和值來自移交對象。

該算法采用所有鍵/值對並具有值的嚴格視圖，這意味着如果找到數組或對象，因此w && typeof w === "object" ，實際部分用於添加額外的鍵/值對。

例如，具有兩個屬性的小對象

{ a: 1, b: [2, 3] }

產量

[
    { a: 1, b: 2 },
    { a: 1, b: 3 }
]

更高級的對象，比如

{ a: 1, b: { c: { d: [2, 3], e: [4, 5] } } }

產生與給定相同的結構

[
    {
        a: 1,
        b: {
            c: { d: 2, e: 4 }
        }
    },
    {
        a: 1,
        b: {
            c: { d: 2, e: 5 }
        }
    },
    {
        a: 1,
        b: {
            c: { d: 3, e: 4 }
        }
    },
    {
        a: 1,
        b: {
            c: { d: 3, e: 5 }
        }
    }
]

Thant意味着，從任何找到的子對象中獲取笛卡爾積並將其與實際值組合。

 const getCartesian = object => Object.entries(object).reduce( (r, [key, value]) => { let temp = []; r.forEach(s => (Array.isArray(value) ? value : [value]).forEach(w => (w && typeof w === "object" ? getCartesian(w) : [w]).forEach(x => temp.push({ ...s, [key]: x }) ) ) ); return temp; }, [{}] ), data = [{ type: "frame", value: ["black", "white", "wood"] }, { type: "finish", value: ["matte", "glossy"] }], result = getCartesian(data) .map(o => ({ attributes: Object.assign([], o).map(({ ...o }) => o) })); console.log(result); console.log(getCartesian({ a: 1, b: { c: { d: [2, 3], e: [4, 5] } } })); 

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

Answer 2

你可以簡化它：

 var variantSections = [ { type: "frame", values: ["black", "white", "wood"] }, { type: "finish", values: ["matte", "glossy"] } ]; // iterate through each variantSection and create objects like {"type": "frame", "value": "black"} var sections = variantSections.map(variant => { return variant.values.map(val => ({type: variant.type, value: val})) }); // then iterate through the two resulting arrays of objects, combining each into the attributes object you want var results = []; for (var i = 0; i < sections[0].length; i++) { for (var j = 0; j < sections[1].length; j++) { results.push({attributes: [sections[0][i], sections[1][j]]}); } } console.log(JSON.parse(JSON.stringify(results)));