Recursively create Object from JSON

Question

I need to create an object from a JSON file. The Input Json file looks like this.

{ 
 "test":{
 "Record":1,
 "RecordValues":{ 
 "Address":"3330 Bay Rd.",
 "City":"Los Angeles",
 "SecondObject":{ 
 "1":"eins",
 "2":"zwei"
 }
 }
 }
}

What i have so far is this function..

var test = [];
function recFunc(obj, parent_id = null) {
 for(var i in obj) {
 if(typeof obj[i] == "object" && obj[i] !== null) {
 test.push({title: i, children: []});
 recFunc(obj[i], (test.length-1));
 }else {
 if(parent_id != null) {
 test[parent_id].children.push({title: (i + " : " + obj[i])});
 }else {
 test.push({title: (i + " : " + obj[i])});
 }
 }
 }
 return test;
}

The output object should be as follows.

[ 
 { "title":"Record : 1" },
 { 
 "title":"RecordValues",
 "children":[ 
 { "title":"Address : 3330 Bay Rd." },
 { "title":"City : Los Angeles" },
 { 
 "title":"SecondObject",
 "children":[ 
 { "title":"1 : eins" },
 { "title":"2 : zwei" }
 ]
 }
 ]
 }
]

• trincot: That target object looks like a very bad design. Can you explain why you need that?
• Vinnecent: @trincot the target object is needed for javascript plugin fancytree

Answer 1

You can use Object.entries and reduce with recursion

let obj = {"test":{"Record":1,"RecordValues":{"Address":"3330 Bay Rd.","City":"Los Angeles","SecondObject":{"1":"eins","2":"zwei"}}}}
let recursive = (obj) =>
 Object.entries(obj).reduce((op,[key,value]) => {
 let final = typeof value === 'object' ? {title:key, children:recursive(value)} 
 : {title: `${key}: ${value}`}
 return op.concat(final)
},[])
console.log(recursive(obj.test))

Answer 2

Here's one possible approach, recursively iterating over the Object.entries:

const input = {
 "test": {
 "Record": 1,
 "RecordValues": {
 "Address": "3330 Bay Rd.",
 "City": "Los Angeles",
 "SecondObject": {
 "1": "eins",
 "2": "zwei"
 }
 }
 }
};
const makeNested = (currInput) => {
 return Object.entries(currInput).map(([key, val]) => (
 typeof val !== 'object'
 ? { title: `${key} : ${val}` }
 : {
 title: key,
 children: makeNested(val)
 }
 ))
};
console.log(makeNested(input.test));

• Vinnecent: I will try that when i come home. Thank you very much :)

Answer 3

You could use Object.entries() and recursively call the function if the nested value is an object:

(The Object(value) === value checks if the value is an object which is not null)

const obj = {test:{Record:1,RecordValues:{Address:"3330 Bay Rd.",City:"Los Angeles",SecondObject:{1:"eins",2:"zwei"}}}};
function transform(obj) {
 return Object.entries(obj).map(([key, value]) => {
 if(Object(value) === value)
 return { title: key, children: transform(value) }
 else
 return { title: `${key} ${value}` }
 })
}
console.log(transform(obj.test))

• Code Maniac: You reached here faster +1
• Code Maniac: and i was messing around using reduce :p i need to practice more about recursion for sure :)