如何与lodash相交? [英] How to get intersection with lodash?

问题描述

我正在尝试在此对象数组中返回匹配的ID:

I am trying to return the matching ids in this array of objects:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1"]

如何仅返回arr中值为1的id?

How can I return just the id with value 1 in arr?

推荐答案

Lodash

最简洁的解决方案可能是使用lodash的 _.intersectionBy ，但这将要求您的 arr2 数组包含一个具有 id 的对象:

Probably the most concise working solution would be using the lodash _.intersectionBy but that would require your arr2 array to contain an object with an id:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =[{id:1}]  // <-- object with the `id`

const result = _.intersectionBy(arr, arr2, 'id');

console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.min.js"></script>

使用 lodash 进行此操作的另一种方法是通过 _.intersectionWith ，不需要对给定的输入进行任何更改:

Another way to do this with lodash would be via _.intersectionWith which does not require any changes on your given inputs:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1"]

const result = _.intersectionWith(arr, arr2, (o,num) => o.id == num);

console.log(result)

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.10/lodash.min.js"></script>

这个想法是为它提供一个自定义函数，以了解如何比较两个数组之间的值.

The idea would be to provide it with a custom function to know how to compare the values between the 2 arrays.

ES6&纯Javascript

如果您只想查找一项，则只能通过 Array.find 使用JS进行此操作:

You can do this with JS only via Array.find if you are looking for just one item:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1"]

const result = arr.find(x => arr2.some(y => x.id == y))
console.log(result)

如果在 arr2 中有更多ID，则可以使用 Array.filter :

You can use Array.filter in the case you have more ids in arr2:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1", "2"]

const result = arr.filter(x => arr2.some(y => x.id == y))
console.log(result)

由于您在arr中有ID，因此您也可以只使用 Array.map :

Since you have the ids in the arr you could also just use Array.map:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1"]

const result = arr2.map(x => arr.find(y => y.id == x))
console.log(result)

@ibrahim mahrir 提到的另一个选项是通过 Array.find & Array.includes :

Another option as mentioned by @ibrahim mahrir would be via Array.find & Array.includes:

const arr = [{id:1,name:'Harry'},{id:2,name:'Bert'}]
const arr2 =["1"]

const result = arr.filter(x => arr2.includes(x.id.toString()))
console.log(result)

这篇关于如何与lodash相交?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！