Question

我有两个数组。
我的数据之一：

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

另一个是int的

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

我想放入tab3中的tab1个值，这些值具有从tab2的值开始的索引。
我曾尝试过一些indexOf // findIndexe
最好的方法是什么？

Answer 1

您可以将tab2数组映射到名为tab3的新数组

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，则可以在列表中搜索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，然后将数据值与索引对应。

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

Answer 4

您可以通过使用对象来执行此操作，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，因为js数组从零开始，所以tab3的键和值将不匹配。

根据来自另一个表的索引获取数组的元素

4 个答案: