Looking for javascript Answers? Try Ask4KnowledgeBase
Looking for javascript Keywords? Try Ask4Keywords

JavaScript Shallow cloning



ES6's Object.assign() function can be used to copy all of the enumerable properties from an existing Object instance to a new one.

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

const clone = Object.assign({}, existing);

This includes Symbol properties in addition to String ones.

Object rest/spread destructuring which is currently a stage 3 proposal provides an even simpler way to create shallow clones of Object instances:

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

const { ...clone } = existing;

If you need to support older versions of JavaScript, the most-compatible way to clone an Object is by manually iterating over its properties and filtering out inherited ones using .hasOwnProperty().

var existing = { a: 1, b: 2, c: 3 };

var clone = {};
for (var prop in existing) {
  if (existing.hasOwnProperty(prop)) {
    clone[prop] = existing[prop];