javascript - 对象值的笛卡尔积(到数组)

Question

假设我有

const item = {
  "Key1": "Value1",
  "Key2": ["Value2", "Value3"]
}

如何将其转换为格式

[["Value1","Value2"],["Value1","Value3"]] 

？

我的做法是:

let array = [];
for (let i of item.Key2){
  array.push([item.Key1,i])
}

只是想知道有没有更短的方法？

Answer 1

// What question mentions
const item = {
  "Key1": "Value1",
  "Key2": ["Value2", "Value3"]
}

let res = item.Key2.map(i => [item.Key1, i])
console.log(res)

// What the world wants!
const item = {
  "Key1": ["ValueA", "ValueB"],
  "Key2": ["Value1", "Value2"]
}

res = item.Key1.reduce((acc, i1) => acc.concat(item.Key2.map(i2 => [i1, i2])), [])
console.log(res)