Question

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我正在寻找一种在对象中合并多个数组道具的有效方法。

对象可以在那里具有多个数组属性：

{
  "col0Codes": [
    "ABC",
    "XYZ",
    "UYA",
    "ZZA",
    "AAW",
    "MYP"
  ],
  "col1Codes": [
    "CNA",
    "ZYA",
    "OIA",
    "POQ",
    "LMO",
    "OPI"
  ],
  "col2Codes": [
    "CNA",
    "ZYA",
    "OIA",
    "POQ",
    "LMO",
    "OPI"
  ],
  "col3Codes": [
    "..."
  ],
  "col4Codes": [
    "..."
  ],
  ...
}

结果：所有代码都在一个数组中

["ABC","XYZ","UYA","ZZA","AAW","MYP","CNA","ZYA","OIA","POQ","LMO","OPI",....]

我尝试使用concat，但这每次都会创建一个新数组并覆盖前一个数组，我觉得这样做并不快且内存效率很高。

let colCodes = []
 for (let i in data) {
 colCodes = colCodes .concat(i)
}
console.log(activityCodes)

我尝试使用push，但是由于某种原因，它不会将所有条目合并到一个数组中，而是在对象中创建一个包含多个道具的数组，如下所示

let colCodes = []
  for (let i in data) {
  colCodes.push(i)
}
console.log(colCodes)
[Array(6), Array(5), ....]

无论如何，我可以使用reduce来做到这一点吗？

Answer 1

您可以获取Object.values()，然后将spreading合并到Array.concat()中：

const data = {"col0Codes":["ABC","XYZ","UYA","ZZA","AAW","MYP"],"col1Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"],"col2Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"]};

const result = [].concat(...Object.values(data));

console.log(result);

Answer 2

一种方法是使用Array.prototype.flat，然后在对象的值上调用它：

const input={"col0Codes":["ABC","XYZ","UYA","ZZA","AAW","MYP"],"col1Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"],"col2Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"]};

console.log(
  Object.values(input).flat()
);

Answer 3

您也可以通过ES6传播简单地Array.reduce Object.values：

const input={"col0Codes":["ABC","XYZ","UYA","ZZA","AAW","MYP"],"col1Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"],"col2Codes":["CNA","ZYA","OIA","POQ","LMO","OPI"]};

console.log(Object.values(input).reduce((r,c) => [...r, ...c]))

Answer 4

您可以尝试

let obj = {"col0Codes": ["ABC","XYZ","UYA","ZZA","AAW","MYP"],
  "col1Codes": ["CNA","ZYA","OIA","POQ","LMO","OPI"],
  "col2Codes": ["CNA","ZYA","OIA","POQ","LMO","OPI"],
  "col3Codes": ["..."],
  "col4Codes": ["..."]
}

let op = [];

for(let key in obj){
  op.push(...obj[key])
}

console.log(op)

合并对象中的多个数组

4 个答案: