JavaScript Array Filtering in Nested Arrays

Question

I have an array that looks something like this:

const arrayObj = [
 {
 id: 1,
 itemsList: [
 {
 name: "Paul",
 },
 {
 name: "Newman",
 },
 ],
 },
 {
 id: 2,
 itemsList: [
 {
 name: "Jack",
 },
 {
 name: "Man",
 },
 ],
 },
]

What I want is to filter the objects whose itemsList contain an object with the name of a certain value. For example, I want to be able to filter out an array with objects whose inner objects with names that contain "ul" (in this case the name Paul contains "ul"), it should give me an output as such:

const outputArray = [
 {
 id: 1,
 itemsList: [
 {
 name: "Paul",
 },
 {
 name: "Newman",
 },
 ]
 }
]

So far, I've only been able to filter out a simple flat array of objects with this function:

function filterByName(array: any, string: any) {
 return array.filter((obj: any) =>
 ["name"].some((key: any) =>
 String(obj[key]).toLowerCase().includes(string.toLowerCase())
 )
 );
}

but I don't know how to apply it to my case.

• mgm793: Does this answer your question? JavaScript - Filter Nested Arrays

Answer 1

Here you can use the some method combined with the includes method

const arrayObj = [{
 id: 1,
 itemsList: [{
 name: "Paul",
 },
 {
 name: "Newman",
 },
 ],
 },
 {
 id: 2,
 itemsList: [{
 name: "Jack",
 },
 {
 name: "Man",
 },
 ],
 },
]
const getFilterArray = (name) => {
 return arrayObj.filter(obj => obj.itemsList.some(x => x.name.toLowerCase().includes(name.toLowerCase())))
}
console.log(getFilterArray("ul"))

Answer 2

const result = arrayObj.filter(({ itemsList }) =>
 itemsList.some(({ name }) => name.toLowerCase().includes('ul')));

Can you try this?