How can I access and process nested objects, arrays, or JSON?

Question

I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)?

For example:

var data = {
    code: 42,
    items: [{
        id: 1,
        name: 'foo'
    }, {
        id: 2,
        name: 'bar'
    }]
};

How could I access the name of the second item in items?

user_3853934 · Answer

Objects and arrays has a lot of built-in methods that can help you with processing data.

Note: in many of the examples I'm using arrow functions. They are similar to function expressions, but they bind the this value lexically.

`Object.keys()`, `Object.values()` (ES 2017) and `Object.entries()` (ES 2017)

Object.keys() returns an array of object's keys, Object.values() returns an array of object's values, and Object.entries() returns an array of object's keys and corresponding values in a format [key, value].

const obj = {
  a: 1
 ,b: 2
 ,c: 3
}

console.log(Object.keys(obj)) // ['a', 'b', 'c']
console.log(Object.values(obj)) // [1, 2, 3]
console.log(Object.entries(obj)) // [['a', 1], ['b', 2], ['c', 3]]

`Object.entries()` with a for-of loop and destructuring assignment

const obj = {
  a: 1
 ,b: 2
 ,c: 3
}

for (const [key, value] of Object.entries(obj)) {
  console.log(`key: ${key}, value: ${value}`)
}

It's very convenient to iterate the result of Object.entries() with a for-of loop and destructuring assignment.

For-of loop lets you iterate array elements. The syntax is for (const element of array) (we can replace const with var or let, but it's better to use const if we don't intend to modify element).

Destructuring assignment lets you extract values from an array or an object and assign them to variables. In this case const [key, value] means that instead of assigning the [key, value] array to element, we assign the first element of that array to key and the second element to value. It is equivalent to this:

for (const element of Object.entries(obj)) {
  const key = element[0]
       ,value = element[1]
}

As you can see, destructuring makes this a lot simpler.

`Array.prototype.every()` and `Array.prototype.some()`

The every() method returns true if the specified callback function returns true for every element of the array. The some() method returns true if the specified callback function returns true for some (at least one) element.

const arr = [1, 2, 3]

// true, because every element is greater than 0
console.log(arr.every(x => x > 0))
// false, because 3^2 is greater than 5
console.log(arr.every(x => Math.pow(x, 2) < 5))
// true, because 2 is even (the remainder from dividing by 2 is 0)
console.log(arr.some(x => x % 2 === 0))
// false, because none of the elements is equal to 5
console.log(arr.some(x => x === 5))

`Array.prototype.find()` and `Array.prototype.filter()`

The find() methods returns the first element which satisfies the provided callback function. The filter() method returns an array of all elements which satisfies the provided callback function.

const arr = [1, 2, 3]

// 2, because 2^2 !== 2
console.log(arr.find(x => x !== Math.pow(x, 2)))
// 1, because it's the first element
console.log(arr.find(x => true))
// undefined, because none of the elements equals 7
console.log(arr.find(x => x === 7))

// [2, 3], because these elements are greater than 1
console.log(arr.filter(x => x > 1))
// [1, 2, 3], because the function returns true for all elements
console.log(arr.filter(x => true))
// [], because none of the elements equals neither 6 nor 7
console.log(arr.filter(x => x === 6 || x === 7))

`Array.prototype.map()`

The map() method returns an array with the results of calling a provided callback function on the array elements.

const arr = [1, 2, 3]

console.log(arr.map(x => x + 1)) // [2, 3, 4]
console.log(arr.map(x => String.fromCharCode(96 + x))) // ['a', 'b', 'c']
console.log(arr.map(x => x)) // [1, 2, 3] (no-op)
console.log(arr.map(x => Math.pow(x, 2))) // [1, 4, 9]
console.log(arr.map(String)) // ['1', '2', '3']

`Array.prototype.reduce()`

The reduce() method reduces an array to a single value by calling the provided callback function with two elements.

const arr = [1, 2, 3]

// Sum of array elements.
console.log(arr.reduce((a, b) => a + b)) // 6
// The largest number in the array.
console.log(arr.reduce((a, b) => a > b ? a : b)) // 3

The reduce() method takes an optional second parameter, which is the initial value. This is useful when the array on which you call reduce() can has zero or one elements. For example, if we wanted to create a function sum() which takes an array as an argument and returns the sum of all elements, we could write it like that:

const sum = arr => arr.reduce((a, b) => a + b, 0)

console.log(sum([]))     // 0
console.log(sum([4]))    // 4
console.log(sum([2, 5])) // 7

user_5113963 · Answer

It's simple explanation:

var data = {
    code: 42,
    items: [{
        id: 1,
        name: 'foo'
    }, {
        id: 2,
        name: 'bar'
    }]
};

/*
1. `data` is object contain `items` object*/
console.log(data);

/*
2. `items` object contain array of two objects as elements*/
console.log(data.items);

/*
3. you need 2nd element of array - the `1` from `[0, 1]`*/
console.log(data.items[1]);

/*
4. and you need value of `name` property of 2nd object-element of array)*/
console.log(data.items[1].name);

user_9445290 · Answer

Here are 4 different methods mentioned to get the javascript object property:

var data = {
  code: 42,
  items: [{
    id: 1,
    name: 'foo'
  }, {
    id: 2,
    name: 'bar'
  }]
};

// Method 1
let method1 = data.items[1].name;
console.log(method1);

// Method 2
let method2 = data.items[1]["name"];
console.log(method2);

// Method 3
let method3 = data["items"][1]["name"];
console.log(method3);

// Method 4  Destructuring
let { items: [, { name: second_name }] } = data;
console.log(second_name);

user_7320391 · Answer

var ourStorage = {


"desk":    {
    "drawer": "stapler"
  },
"cabinet": {
    "top drawer": { 
      "folder1": "a file",
      "folder2": "secrets"
    },
    "bottom drawer": "soda"
  }
};
ourStorage.cabinet["top drawer"].folder2; // Outputs -> "secrets"

or

//parent.subParent.subsubParent["almost there"]["final property"]

Basically, use a dot between each descendant that unfolds underneath it and when you have object names made out of two strings, you must use the ["obj Name"] notation. Otherwise, just a dot would suffice;

Source: https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/accessing-nested-objects

to add to this, accessing nested Arrays would happen like so:

var ourPets = [
  {
    animalType: "cat",
    names: [
      "Meowzer",
      "Fluffy",
      "Kit-Cat"
    ]
  },
  {
    animalType: "dog",
    names: [
      "Spot",
      "Bowser",
      "Frankie"
    ]
  }
];
ourPets[0].names[1]; // Outputs "Fluffy"
ourPets[1].names[0]; // Outputs "Spot"

Source: https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/basic-javascript/accessing-nested-arrays/

Another more useful document depicting the situation above: https://developer.mozilla.org/en-US/docs/Learn/JavaScript/Objects/Basics#Bracket_notation

Property access via dot walking: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Property_Accessors#Dot_notation

user_6318702 · Answer

Accessing dynamically multi levels object.

var obj = {
  name: "john doe",
  subobj: {
    subsubobj: {
      names: "I am sub sub obj"
    }
  }
};

var level = "subobj.subsubobj.names";
level = level.split(".");

var currentObjState = obj;

for (var i = 0; i < level.length; i++) {
  currentObjState = currentObjState[level[i]];
}

console.log(currentObjState);

Working fiddle: https://jsfiddle.net/andreitodorut/3mws3kjL/

user_3626796 · Answer

Just in case, anyone's visiting this question in 2017 or later and looking for an easy-to-remember way, here's an elaborate blog post on Accessing Nested Objects in JavaScript without being bamboozled by

Cannot read property 'foo' of undefined error

1. Oliver Steele's nested object access pattern

The easiest and the cleanest way is to use Oliver Steele's nested object access pattern

const name = ((user || {}).personalInfo || {}).name;

With this notation, you'll never run into

Cannot read property 'name' of undefined.

You basically check if user exists, if not, you create an empty object on the fly. This way, the next level key will always be accessed from an object that exists or an empty object, but never from undefined.

2. Access Nested Objects Using Array Reduce

To be able to access nested arrays, you can write your own array reduce util.

const getNestedObject = (nestedObj, pathArr) => {
    return pathArr.reduce((obj, key) =>
        (obj && obj[key] !== 'undefined') ? obj[key] : undefined, nestedObj);
}

// pass in your object structure as array elements
const name = getNestedObject(user, ['personalInfo', 'name']);

// to access nested array, just pass in array index as an element the path array.
const city = getNestedObject(user, ['personalInfo', 'addresses', 0, 'city']);
// this will return the city from the first address item.

There is also an excellent type handling minimal library typy that does all this for you.

user_860099 · Answer

Dynamic approach

In below deep(data,key) function, you can use arbitrary key string - in your case items[1].name (you can use array notation [i] at any level) - if key is invalid then undefined is return.

let deep = (o,k) => k.split('.').reduce((a,c,i) => {
    let m=c.match(/(.*?)$$(\d*)$$/);
    if(m && a!=null && a[m[1]]!=null) return a[m[1]][+m[2]];
    return a==null ? a: a[c];
},o);

// TEST

let key = 'items[1].name' // arbitrary deep-key

let data = {
    code: 42,
    items: [{ id: 11, name: 'foo'}, { id: 22, name: 'bar'},]
};

console.log( key,'=', deep(data,key) );

user_2435179 · Answer

In 2020, you can use @babel/plugin-proposal-optional-chaining it is very easy to access nested values in an object.

 const obj = {
 foo: {
   bar: {
     baz: class {
   },
  },
 },
};

const baz = new obj?.foo?.bar?.baz(); // baz instance

const safe = new obj?.qux?.baz(); // undefined
const safe2 = new obj?.foo.bar.qux?.(); // undefined

https://babeljs.io/docs/en/babel-plugin-proposal-optional-chaining

https://github.com/tc39/proposal-optional-chaining

user_7584019 · Answer

You can use the syntax jsonObject.key to access the the value. And if you want access a value from an array, then you can use the syntax jsonObjectArray[index].key.

Here are the code examples to access various values to give you the idea.

var data = {
    code: 42,
    items: [{
        id: 1,
        name: 'foo'
    }, {
        id: 2,
        name: 'bar'
    }]
};

// if you want 'bar'
console.log(data.items[1].name);

// if you want array of item names
console.log(data.items.map(x => x.name));

// get the id of the item where name = 'bar'
console.log(data.items.filter(x => (x.name == "bar") ? x.id : null)[0].id);

user_5283424 · Answer

// const path = 'info.value[0].item'
// const obj = { info: { value: [ { item: 'it works!' } ], randominfo: 3 }  }
// getValue(path, obj)

export const getValue = ( path , obj) => {
  const newPath = path.replace(/\]/g, "")
  const arrayPath = newPath.split(/[\[\.]+/) || newPath;

  const final = arrayPath.reduce( (obj, k) => obj ?  obj[k] : obj, obj)
  return final;
}

user_1030413 · Answer

Here is an answer using object-scan.

When accessing a single entry, this answer doesn't really provide much benefit over vanilla javascript. However interacting with multiple fields at the same time this answer can be more performant.

Here is how you could interact with a single field

// const objectScan = require('object-scan');

const data = { code: 42, items: [{ id: 1, name: 'foo' }, { id: 2, name: 'bar' }] };

const get = (haystack, needle) => objectScan([needle], {
  abort: true,
  rtn: 'value'
})(haystack);

const set = (haystack, needle, value) => objectScan([needle], {
  abort: true,
  rtn: 'bool',
  filterFn: ({ parent, property }) => {
    parent[property] = value;
    return true;
  }
})(haystack);

console.log(get(data, 'items[1].name'));
// => bar

console.log(set(data, 'items[1].name', 'foo2'));
// => true
console.log(data);
// => { code: 42, items: [ { id: 1, name: 'foo' }, { id: 2, name: 'foo2' } ] }

.as-console-wrapper {max-height: 100% !important; top: 0}

Disclaimer: I'm the author of object-scan

and here is how you could interact with multiple fields at the same time

// const objectScan = require('object-scan');

const data = { code: 42, items: [{ id: 1, name: 'foo' }, { id: 2, name: 'bar' }] };

const get = (haystack, ...needles) => objectScan(needles, {
  joined: true,
  rtn: 'entry'
})(haystack);

const set = (haystack, actions) => objectScan(Object.keys(actions), {
  rtn: 'count',
  filterFn: ({ matchedBy, parent, property }) => {
    matchedBy.forEach((m) => {
      parent[property] = actions[m];
    })
    return true;
  }
})(haystack);

console.log(get(data, 'items[0].name', 'items[1].name'));
// => [ [ 'items[1].name', 'bar' ], [ 'items[0].name', 'foo' ] ]

console.log(set(data, {
  'items[0].name': 'foo1',
  'items[1].name': 'foo2'
}));
// => 2
console.log(data);
// => { code: 42, items: [ { id: 1, name: 'foo1' }, { id: 2, name: 'foo2' } ] }

.as-console-wrapper {max-height: 100% !important; top: 0}

Disclaimer: I'm the author of object-scan

And here is how one could find an entity in a deeply nested object searching by id (as asked in comment)

// const objectScan = require('object-scan');

const myData = { code: 42, items: [{ id: 1, name: 'aaa', items: [{ id: 3, name: 'ccc' }, { id: 4, name: 'ddd' }] }, { id: 2, name: 'bbb', items: [{ id: 5, name: 'eee' }, { id: 6, name: 'fff' }] }] };

const findItemById = (haystack, id) => objectScan(['**(^items$).id'], {
  abort: true,
  useArraySelector: false,
  rtn: 'parent',
  filterFn: ({ value }) => value === id
})(haystack);

console.log(findItemById(myData, 5));
// => { id: 5, name: 'eee' }

.as-console-wrapper {max-height: 100% !important; top: 0}

Disclaimer: I'm the author of object-scan

user_6243352 · Answer

If you're trying to find a path in a JSON string, you can dump your data into https://jsonpathfinder.com and click on the GUI elements. It'll generate the JS syntax for the path to the element.

Beyond that, for any arrays you might want to iterate, replace the relevant array offset indices like [0] with a loop.

Here's a simpler version of the tool you can run here, or at https://ggorlen.github.io/json-dive/. Click the node you want to copy the path to your clipboard.

/* code minified to make the tool easier to run without having to scroll */                                                         let bracketsOnly=!1,lastHighlighted={style:{}};const keyToStr=t=>!bracketsOnly&&/^[a-zA-Z_$][a-zA-Z$_\d]*$/.test(t)?`.${toHTML(t)}`:`["${toHTML(t)}"]`,pathToData=t=>`data-path="data${t.join("")}"`,htmlSpecialChars={"&":"&","<":"<",">":">",'"':""","'":"'","	":"\t","
":"\r","
":"\n"," ":" "},toHTML=t=>(""+t).replace(/[&<>"'	
 ]/g,t=>htmlSpecialChars[t]),makeArray=(t,e)=>`
  [
    ${t.map((t,a)=>{e.push(`[${a}]`);const n=`
        ${pathify(t,e).trim()},
      `;return e.pop(),n}).join("")}
  ]
`,makeObj=(t,e)=>`
  {
    ${Object.entries(t).map(([t,a])=>{e.push(keyToStr(t));const n=`
        "${toHTML(t)}": ${pathify(a,e).trim()},
      `;return e.pop(),n}).join("")}
  }
`,pathify=(t,e=[])=>Array.isArray(t)?makeArray(t,e):"object"==typeof t&&t!=null?makeObj(t,e):toHTML("string"==typeof t?`"${t}"`:t),defaultJSON='{
  "corge": "test JSON... \n   asdf\t asdf",
  "foo-bar": [
    {"id": 42},
    [42, {"foo": {"baz": {"ba  r<>!\t": true, "4quux": "garply"}}}]
  ]
}',$=document.querySelector.bind(document),$$=document.querySelectorAll.bind(document),resultEl=$("#result"),pathEl=$("#path"),tryToJSON=t=>{try{resultEl.innerHTML=pathify(JSON.parse(t)),$("#error").innerText=""}catch(t){resultEl.innerHTML="",$("#error").innerText=t}},copyToClipboard=t=>{const e=document.createElement("textarea");e.innerText=t,document.body.appendChild(e),e.select(),document.execCommand("copy"),document.body.removeChild(e)},flashAlert=(t,e=2e3)=>{const a=document.createElement("div");a.textContent=t,a.classList.add("alert"),document.body.appendChild(a),setTimeout(()=>a.remove(),e)},handleClick=t=>{t.stopPropagation(),copyToClipboard(t.target.dataset.path),flashAlert("copied!"),$("#path-out").textContent=t.target.dataset.path},handleMouseOut=t=>{lastHighlighted.style.background="transparent",pathEl.style.display="none"},handleMouseOver=t=>{pathEl.textContent=t.target.dataset.path,pathEl.style.left=`${t.pageX+30}px`,pathEl.style.top=`${t.pageY}px`,pathEl.style.display="block",lastHighlighted.style.background="transparent",(lastHighlighted=t.target.closest("li")).style.background="#0ff"},handleNewJSON=t=>{tryToJSON(t.target.value),[...$$("#result *")].forEach(t=>{t.addEventListener("click",handleClick),t.addEventListener("mouseout",handleMouseOut),t.addEventListener("mouseover",handleMouseOver)})};$("textarea").addEventListener("change",handleNewJSON),$("textarea").addEventListener("keyup",handleNewJSON),$("textarea").value=defaultJSON,$("#brackets").addEventListener("change",t=>{bracketsOnly=!bracketsOnly,handleNewJSON({target:{value:$("textarea").value}})}),handleNewJSON({target:{value:defaultJSON}});

/**/                                                                                       *{box-sizing:border-box;font-family:monospace;margin:0;padding:0}html{height:100%}#path-out{background-color:#0f0;padding:.3em}body{margin:0;height:100%;position:relative;background:#f8f8f8}textarea{width:100%;height:110px;resize:vertical}#opts{background:#e8e8e8;padding:.3em}#opts label{padding:.3em}#path{background:#000;transition:all 50ms;color:#fff;padding:.2em;position:absolute;display:none}#error{margin:.5em;color:red}#result ul{list-style:none}#result li{cursor:pointer;border-left:1em solid transparent}#result li:hover{border-color:#ff0}.alert{background:#f0f;padding:.2em;position:fixed;bottom:10px;right:10px}

                                                                                                    brackets only: 
click a node to copy path to clipboard

Unminified (also available on GitHub):

let bracketsOnly = false;
let lastHighlighted = {style: {}};

const keyToStr = k =>
  !bracketsOnly && /^[a-zA-Z_$][a-zA-Z$_\d]*$/.test(k) 
    ? `.${toHTML(k)}`
    : `["${toHTML(k)}"]`
;
const pathToData = p => `data-path="data${p.join("")}"`;

const htmlSpecialChars = {
  "&": "&",
  "<": "<",
  ">": ">",
  '"': """,
  "'": "'",
  "	": "\t",
  "
": "\r",
  "
": "\n",
  " ": " ",
};
const toHTML = x => ("" + x)
  .replace(/[&<>"'	
 ]/g, m => htmlSpecialChars[m])
;

const makeArray = (x, path) => `
  [
    ${x.map((e, i) => {
      path.push(`[${i}]`);
      const html = `
        ${pathify(e, path).trim()},
      `;
      path.pop();
      return html;
    }).join("")}
  ]
`;
const makeObj = (x, path) => `
  {
    ${Object.entries(x).map(([k, v]) => {
      path.push(keyToStr(k));
      const html = `
        "${toHTML(k)}": ${pathify(v, path).trim()},
      `;
      path.pop();
      return html;
    }).join("")}
  }
`;

const pathify = (x, path=[]) => {
  if (Array.isArray(x)) {
    return makeArray(x, path);
  }
  else if (typeof x === "object" && x !== null) {
    return makeObj(x, path);
  }
  
  return toHTML(typeof x === "string" ? `"${x}"` : x);
};

const defaultJSON = `{
  "corge": "test JSON... \n   asdf\t asdf",
  "foo-bar": [
    {"id": 42},
    [42, {"foo": {"baz": {"ba  r<>!\t": true, "4quux": "garply"}}}]
  ]
}`;

const $ = document.querySelector.bind(document);
const $$ = document.querySelectorAll.bind(document);
const resultEl = $("#result");
const pathEl = $("#path");

const tryToJSON = v => {
  try {
    resultEl.innerHTML = pathify(JSON.parse(v));
    $("#error").innerText = "";
  }
  catch (err) {
    resultEl.innerHTML = "";
    $("#error").innerText = err;
  }
};

const copyToClipboard = text => {
  const ta = document.createElement("textarea");
  ta.innerText = text;
  document.body.appendChild(ta);
  ta.select();
  document.execCommand("copy");
  document.body.removeChild(ta);
};

const flashAlert = (text, timeoutMS=2000) => {
  const alert = document.createElement("div");
  alert.textContent = text;
  alert.classList.add("alert");
  document.body.appendChild(alert);
  setTimeout(() => alert.remove(), timeoutMS);
};

const handleClick = e => {
  e.stopPropagation();
  copyToClipboard(e.target.dataset.path);
  flashAlert("copied!");
  $("#path-out").textContent = e.target.dataset.path;
};

const handleMouseOut = e => {
  lastHighlighted.style.background = "transparent";
  pathEl.style.display = "none";
};

const handleMouseOver = e => {
  pathEl.textContent = e.target.dataset.path;
  pathEl.style.left = `${e.pageX + 30}px`;
  pathEl.style.top = `${e.pageY}px`;
  pathEl.style.display = "block";
  lastHighlighted.style.background = "transparent";
  lastHighlighted = e.target.closest("li");
  lastHighlighted.style.background = "#0ff";
};

const handleNewJSON = e => {
  tryToJSON(e.target.value);
  [...$$("#result *")].forEach(e => {
    e.addEventListener("click", handleClick);
    e.addEventListener("mouseout", handleMouseOut);
    e.addEventListener("mouseover", handleMouseOver);
  });
};
$("textarea").addEventListener("change", handleNewJSON);
$("textarea").addEventListener("keyup", handleNewJSON);
$("textarea").value = defaultJSON;
$("#brackets").addEventListener("change", e => {
  bracketsOnly = !bracketsOnly;
  handleNewJSON({target: {value: $("textarea").value}});
});
handleNewJSON({target: {value: defaultJSON}});

* {
  box-sizing: border-box;
  font-family: monospace;
  margin: 0;
  padding: 0;
}

html {
  height: 100%;
}

#path-out {
  background-color: #0f0;
  padding: 0.3em;
}

body {
  margin: 0;
  height: 100%;
  position: relative;
  background: #f8f8f8;
}

textarea {
  width: 100%;
  height: 110px;
  resize: vertical;
}

#opts {
  background: #e8e8e8;
  padding: 0.3em;
}
#opts label {
  padding: 0.3em;
}

#path {
  background: black;
  transition: all 0.05s;
  color: white;
  padding: 0.2em;
  position: absolute;
  display: none;
}

#error {
  margin: 0.5em;
  color: red;
}

#result ul {
  list-style: none;
}

#result li {
  cursor: pointer;
  border-left: 1em solid transparent;
}
#result li:hover {
  border-color: #ff0;
}

.alert {
  background: #f0f;
  padding: 0.2em;
  position: fixed;
  bottom: 10px;
  right: 10px;
}


  
  
    
      brackets only: 
    
  
  click a node to copy path to clipboard

This isn't intended as a substitute for learning how to fish but can save time once you do know.

user_9570734 · Answer

this is how i have done this.

 let groups = [
        {
            id:1,
            title:"Group 1",
            members:[
                {
                    id:1,
                    name:"Aftab",
                    battry:'10%'
                },
                {
                    id:2,
                    name:"Jamal",
                },
                {
                    id:3,
                    name:"Hamid",
                },
                {
                    id:4,
                    name:"Aqeel",
                },
            ]
        },
        {
            id:2,
            title:"Group 2",
            members:[
                {
                    id:1,
                    name:"Aftab",
                    battry:'10%'
                },
                {
                    id:2,
                    name:"Jamal",
                    battry:'10%'
                },
                {
                    id:3,
                    name:"Hamid",
                },
               
            ]
        },
        {
            id:3,
            title:"Group 3",
            members:[
                {
                    id:1,
                    name:"Aftab",
                    battry:'10%'
                },
                
                {
                    id:3,
                    name:"Hamid",
                },
                {
                    id:4,
                    name:"Aqeel",
                },
            ]
        }
    ]
    
    groups.map((item) => {
      //  if(item.id == 2){
        item.members.map((element) => {
             if(element.id == 1){
                 element.battry="20%"
             }
         })
        //}
    })
    
    groups.forEach((item) => {
        item.members.forEach((item) => {
            console.log(item)
    })
    })

user_13955215 · Answer

what you need to do is really simple and it can be achieved trough recursivity:

const json_object = {
        "item1":{
            "name": "apple",
            "value": 2,
        },
        "item2":{
            "name": "pear",
            "value": 4,
        },
        "item3":{
            "name": "mango",
            "value": 3,
            "prices": {
                "1": "9$",
                "2": "59$",
                "3": "1$"
            }
        }
    }
    
    function walkJson(json_object){
        for(obj in json_object){
            if(typeof json_object[obj] === 'string'){
                console.log(`${obj}=>${json_object[obj]}`);
            }else{
                console.log(`${obj}=>${json_object[obj]}`);
                walkJson(json_object[obj]);
            }
        }           
    }
    
    walkJson(json_object);

user_7408350 · Answer

My stringdata is coming from PHP file but still, I indicate here in var. When i directly take my json into obj it will nothing show thats why i put my json file as

var obj=JSON.parse(stringdata); so after that i get message obj and show in alert box then I get data which is json array and store in one varible ArrObj then i read first object of that array with key value like this ArrObj[0].id

     var stringdata={
        "success": true,
        "message": "working",
        "data": [{
                  "id": 1,
                  "name": "foo"
         }]
      };

                var obj=JSON.parse(stringdata);
                var key = "message";
                alert(obj[key]);
                var keyobj = "data";
                var ArrObj =obj[keyobj];

                alert(ArrObj[0].id);

user_4450209 · Answer

Using lodash would be good solution

Ex:

var object = { 'a': { 'b': { 'c': 3 } } };                                                                                               
_.get(object, 'a.b.c');                                                                                             
// => 3

How can I access and process nested objects, arrays, or JSON?

31 Answers

Object.keys(), Object.values() (ES 2017) and Object.entries() (ES 2017)

Object.entries() with a for-of loop and destructuring assignment

Array.prototype.every() and Array.prototype.some()

Array.prototype.find() and Array.prototype.filter()

Array.prototype.map()

Array.prototype.reduce()

Here are 4 different methods mentioned to get the javascript object property:

1. Oliver Steele's nested object access pattern

2. Access Nested Objects Using Array Reduce

Dynamic approach

`Object.keys()`, `Object.values()` (ES 2017) and `Object.entries()` (ES 2017)

`Object.entries()` with a for-of loop and destructuring assignment

`Array.prototype.every()` and `Array.prototype.some()`

`Array.prototype.find()` and `Array.prototype.filter()`

`Array.prototype.map()`

`Array.prototype.reduce()`