JS - 從 object 中，為某個鍵的每個值返回 object

Question

從這個 object：

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

我想得到這個：

{"a": "a", "b": "b", "c":1}
{"a": "a", "b": "b", "c":2}
{"a": "a", "b": "b", "c":3}

我能怎么做？

Answer 1

You can map the data.c , and get the a , b from the origin object and c from the map callback item parameter.

 const data = {"a": "a", "b": "b", "c": [1,2,3]} const result = data.c.map(i => ({ a: data.a, b: data.b, c: i, })) console.log(result)

Answer 2

Map over object[c]並返回 object object 本身的副本 + 當前值：

 let expand = (obj, key) => obj[key].map(val => ({...obj, [key]: val})) test = {"a": "a", "b": "b", "c": [1,2,3]} result = expand(test, 'c') console.log(result)

Answer 3

首先，您應該檢查obj[key]是否是一個數組。 如果是，繼續映射，否則只返回 object

 const transform = (obj, key) => { if (.Array.isArray(obj[key])) return obj return obj[key].map(val => ({..,obj: [key]. val })) } console:log(transform({ a, "a": b, "b": c, "c" }. "c")) console:log(transform({ a, "a": b, "b": c, [1, 2, 3] }. "c")) console:log(transform({ a, "a": b, "b": d, [4, 5, 6] }, "d"))