In-depth understanding of Object Clone and javascriptclone in JavaScript

Source: Internet
Author: User
Tags hasownproperty

In-depth understanding of Object Clone and javascriptclone in JavaScript

JavaScript does not directly provide the Object Clone method. Therefore, when object B is changed in the following code, object a is changed.

A = {k1: 1, k2: 2, k3: 3 };

B =;

B. k2 = 4;

If you only want to change B and keep a unchanged, You need to copy object.

Copying objects with jQuery

When jQuery can be used, the extend method provided by jQuery can be used to copy objects.

A = {k1: 1, k2: 2, k3: 3 };

B = {};

$. Extend (B, );

Custom clone () method for object Replication

The following method is the basic idea of object replication.

Object.prototype.clone = function() { var copy = (this instanceof Array) ? [] : {}; for (attr in this) {  if (!obj.hasOwnProperty(attr)) continue;  copy[attr] = (typeof this[i] == "object")?obj[attr].clone():obj[attr]; }  return copy;};a = {k1:1, k2:2, k3:3};b = a.clone();

The example below is more comprehensive and applies to Deep Copy of most objects ).

function clone(obj) {  // Handle the 3 simple types, and null or undefined  if (null == obj || "object" != typeof obj) return obj;  // Handle Date  if (obj instanceof Date) {    var copy = new Date();    copy.setTime(obj.getTime());    return copy;  }  // Handle Array  if (obj instanceof Array) {    var copy = [];    for (var i = 0, var len = obj.length; i < len; ++i) {      copy[i] = clone(obj[i]);    }    return copy;  }  // Handle Object  if (obj instanceof Object) {    var copy = {};    for (var attr in obj) {      if (obj.hasOwnProperty(attr)) copy[attr] = clone(obj[attr]);    }    return copy;  }  throw new Error("Unable to copy obj! Its type isn't supported.");}

The above in-depth understanding of Object replication (Object Clone) in JavaScript is all the content shared by the editor. I hope it can be a reference for you and a lot of support for helping customers.

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