How to find a object in a nested array using recursion in JS

Question

Consider the following deeply nested array:

const array = [
    {
        id: 1,
        name: \"bla\",
        children: [
            {
                id:         


        

Answer 1

You might also use recursion with Array.find like below

const array=[{id:1,name:"bla",children:[{id:23,name:"bla",children:[{id:88,name:"bla"},{id:99,name:"bla"}]},{id:43,name:"bla"},{id:45,name:"bla",children:[{id:43,name:"bla"},{id:46,name:"bla"}]}]},{id:12,name:"bla",children:[{id:232,name:"bla",children:[{id:848,name:"bla"},{id:959,name:"bla"}]},{id:433,name:"bla"},{id:445,name:"bla",children:[{id:443,name:"bla"},{id:456,name:"bla",children:[{id:97,name:"bla"},{id:56,name:"bla"}]}]}]},{id:15,name:"bla",children:[{id:263,name:"bla",children:[{id:868,name:"bla"},{id:979,name:"bla"}]},{id:483,name:"bla"},{id:445,name:"bla",children:[{id:423,name:"bla"},{id:436,name:"bla"}]}]}];


function findById(arr, id, nestingKey) {
  
  // if empty array then return
  if(arr.length == 0) return
  
  // return element if found else collect all children(or other nestedKey) array and run this function
  return arr.find(d => d.id == id) 
      || findById(arr.flatMap(d => d[nestingKey] || []), id) 
      || 'Not found'
}

console.log(findById(array, 12, 'children'))

console.log(findById(array, 483, 'children'))

console.log(findById(array, 1200, 'children'))