access object property dynamically javascript code example

Example 1: javascript dynamically access object property

var person ={"first_name":"Billy","last_name":"Riley"};
var property_name="first_name";
alert(person[property_name]); //Dynamically access object property with bracket notation

Example 2: dynamic properties instead javascript

var foo = { pName1 : 1, pName2 : [1, {foo : bar }, 3] , ...}

var name = "pName"
var num  = 1;

foo[name + num]; // 1

// -- 

var a = 2;
var b = 1;
var c = "foo";

foo[name + a][b][c]; // bar

Example 3: dynamic object property name javascript

let me = {
  name: 'samantha',
};

// 1. Dot notation
me.name; // samantha

// 2. Bracket notation (string key)
me['name']; // samantha

// 3. Bracket notation (variable key)
let key = 'name';
me[key]; // samantha

Example 4: access object property dynamically javascript

let nestedObject = { levelOne: { levelTwo: { levelThree : 'final destination'} } }

const prop1 = 'levelOne';
const prop2 = 'levelTwo';
const prop3 = 'levelThree';

var destination = nestedObject[prop1][prop2][prop3];

// destination = 'final destination'