需要用角度打字稿格式化我的数组

Question

如下所示获取我的数组

let myArr=[["529256","88163","50210","11843","19404","39807","25177"]]

我必须在下面格式化

let formatArr=[
  ["529256", undefined, undefined, undefined, undefined, undefined, undefined],
  [undefined, "88163", undefined, undefined, undefined, undefined, undefined],
  [undefined, undefined, "50210", undefined, undefined, undefined, undefined],
  [undefined, undefined, undefined, "11843", undefined, undefined, undefined],
  [undefined, undefined, undefined, undefined, "19404", undefined, undefined],
  [undefined, undefined, undefined, undefined, undefined, "39807", undefined],
  [undefined, undefined, undefined, undefined, undefined, undefined, "25177"]
]

Answer 1

flat() 方法创建一个新数组，其中所有子数组元素递归连接到指定深度。

let myArr = [
  ["529256", "88163", "50210", "11843", "19404", "39807", "25177"]
]

let formatArray = myArr.flat(1).map((number, index, array) => {
  const size = array.length;
  return new Array(size).fill(undefined).map((item, innerIndex) => {
    if (index === innerIndex) {
      return number;
    } else {
      return undefined
    }
  });
})
console.log(formatArray)

Answer 2

你可以简单地使用reduce函数来实现这个

let myArr = [
  ["529256", "88163", "50210", "11843", "19404", "39807", "25177"]
]

const newArray = myArr[0].reduce((prev, next, index) => {
  let arr = Array(myArr[0].length).fill(undefined)
  arr[index] = next
  return [...prev, arr]
},[])

console.log(newArray)