How to turn nested objects into array?

Question

I am struggling to what seems to be a trivial task. I need to iterate over this nested object...

[
 {
 "id": "1",
 "name": "Level 1",
 "parent": null,
 "expanded": true,
 "title": "Level 1",
 "children": [
 {
 "id": "2",
 "name": "Level 2",
 "parent": 1,
 "expanded": true,
 "title": "Level 2",
 "children": [
 {
 "id": "3",
 "name": "Level 3",
 "parent": 2,
 "expanded": true,
 "title": "Level 3"
 }
 ]
 }
 ]
 }
]

... and end up with below structure.

I have tried .map(Object.values) but that only seems to work partially. What is the most optimal way to get there? What are the alternatives?

 [
 { id: '1', name: 'Level 1', parent: null, expanded: true },
 { id: '2', name: 'Level 2', parent: 1, expanded: true },
 { id: '3', name: 'Level 3', parent: 2, expanded: true }
]

• T.J. Crowder: What do you struggles look like? That would help us help you.
• Jimish Fotariya: Instead of asking for direct solution, Provide more details on what aproach you're taking.
• Nina Scholz: btw, your id and parent properties do not match typewise.
• Alexey Shevelyov: @JimishFotariya was looking for ideas or directions. I have tried .map as well as constructing the objects falling into a rabbit hole. Wanted some clear ideas / directions. Sorry if I came across as looking for a straight up answer.

Answer 1

You could take a recursive approach and seperate children from the objects and map the rest object and the flat children.

var getFlat = ({ children = [], ...rest }) => [rest, ...children.flatMap(getFlat)],
 data = [{ id: "1", name: "Level 1", parent: null, expanded: true, title: "Level 1", children: [{ id: "2", name: "Level 2", parent: 1, expanded: true, title: "Level 2", children: [{ id: "3", name: "Level 3", parent: 2, expanded: true, title: "Level 3" }] }] }],
 result = data.flatMap(getFlat);
console.log(result)

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Answer 2

You can try this way, this will work for you

let nestedArrayObj = [{ "id": "1", "name": "Level 1", "parent": null, "expanded": true, "title": "Level 1", "children": [{ "id": "2", "name": "Level 2", "parent": 1, "expanded": true, "title": "Level 2", "children": [{ "id": "3", "name": "Level 3", "parent": 2, "expanded": true, "title": "Level 3" }] }] }]
let nestedArray = []
function nestedArrayFn(nestedArrayObj) {
 nestedArrayObj.forEach(obj => {
 nestedArray.push(JSON.parse(JSON.stringify(obj, ['id', 'name', 'parent', 'expanded'])))
 if (obj.children && obj.children.length) {
 nestedArrayFn(obj.children)
 }
 })
 return nestedArray
}
let finalArray = nestedArrayFn(nestedArrayObj)
console.log(finalArray)

Answer 3

Using a recursive approach with the function Array.prototype.map.

let a = [{ id: "1", name: "Level 1", parent: null, expanded: true, title: "Level 1", children: [{ id: "2", name: "Level 2", parent: 1, expanded: true, title: "Level 2", children: [{ id: "3", name: "Level 3", parent: 2, expanded: true, title: "Level 3" }] }] }];
function loop(arr) {
 let nested = [];
 return [].concat(arr.map(({id, name, parent, expanded, children}) => {
 if (children) nested = nested.concat(loop(children));
 return {id, name, parent, expanded};
 }), nested);
}
console.log(loop(a));

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Answer 4

You can build a recursive function to tackle this.

var data = [ { "id": "1", "name": "Level 1", "parent": null, "expanded": true, "title": "Level 1", "children": [ { "id": "2", "name": "Level 2", "parent": 1, "expanded": true, "title": "Level 2", "children": [ { "id": "3", "name": "Level 3", "parent": 2, "expanded": true, "title": "Level 3" } ] } ] }];
let resolve= (array, modified = []) =>{
 array.forEach(({children, ...rest})=>{
 modified.push(rest);
 if(children) resolve(children, modified);
 });
 return modified;
}
console.log(resolve(data))

Answer 5

You need to iterate through nested children recursively, like that:

const obj = {"id":"1","name":"Level 1","parent":null,"expanded":true,"title":"Level 1","children":[{"id":"2","name":"Level 2","parent":1,"expanded":true,"title":"Level 2","children":[{"id":"3","name":"Level 3","parent":2,"expanded":true,"title":"Level 3"}]}]},
 
 flattenObj = ({title, children, ...rest}) => 
 ([rest, ...(children ? children.flatMap(flattenObj) : [])])
 
console.log(flattenObj(obj))

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