根据来自另一个表的索引获取数组的元素

Question

我有两个数组。
一个与我的数据：

var tab1 = ["one","two","three","four","five","six","seven","eight","nine","ten","eleven","twelve","thirteen","fourteen","fifteen","sixteen","seventeen","eighteen","nineteen","twenty"];

另一个带有 int：

var tab2 = [1,4,5,8,12,15,18];

我想放入tab1中的tab3值，这些值具有来自tab2值的索引。
我曾尝试使用一些indexOf // findIndexe
做到这一点的最佳方法是什么？

Answer 1

您可以将tab2数组映射到名为tab3的新数组中

 const tab1 = [ "one","two","three","four","five","six","seven", "eight","nine","ten","eleven","twelve","thirteen","fourteen", "fifteen","sixteen","seventeen","eighteen","nineteen","twenty" ]; const tab2 = [1,4,5,8,12,15,18]; const tab3 = tab2.map(index => tab1[index]) console.log(tab3)

问题要求索引。 但是，如果所需的答案是数字的实际字符串表示形式，则您将在列表中搜索index-1项。

 const tab1 = [ "one","two","three","four","five","six","seven", "eight","nine","ten","eleven","twelve","thirteen","fourteen", "fifteen","sixteen","seventeen","eighteen","nineteen","twenty" ]; const tab2 = [1,4,5,8,12,15,18]; const tab3 = tab2.map(index => tab1[index -1]) console.log(tab3)

Answer 2

使用Array.map() ：

 const tab1 = ["one","two","three","four","five","six","seven","eight","nine","ten","eleven","twelve","thirteen","fourteen","fifteen","sixteen","seventeen","eighteen","nineteen","twenty"]; const tab2 = [1,4,5,8,12,15,18]; const tab3 = tab2.map(num => tab1[num - 1]); console.log(tab3);

Answer 3

让我们迭代包含索引的数组并将数据的值对应于索引。

tab2.forEach(i => { 
    tab3.push(tab1[i]) 
})

Answer 4

你可以通过使用对象来做到这一点，因为 js 中没有索引数组。

var tab1 = ["one","two","three","four","five","six","seven","eight","nine","ten","eleven","twelve","thirteen","fourteen","fifteen","sixteen","seventeen","eighteen","nineteen","twenty"];

var tab2 = [1,4,5,8,12,15,18];
var tab3 = {};
tab2.forEach((val) => {
    tab3[val] = tab1[val];
})

console.log(tab3);

当然，tab3 的键和值不会匹配，因为 js 数组是从零开始的。