Three practical methods for JavaScript Object cloning

Method 1

View sourceprint? 01 function clone (obj ){

02 var o;

03 if (typeof obj = "object "){

04 if (obj = null ){

05 o = null;

06} else {

07 if (obj instanceof Array ){

08 o = [];

09 for (var I = 0, len = obj. length; I <len; I ++ ){

10 o. push (clone (obj [I]);

11}

12} else {

13 o = {};

14 for (var k in obj ){

15 o [k] = clone (obj [k]);

16}

17}

18}

19} else {

20 o = obj;

21}

22 return o;

23}

Method 2

View sourceprint? 01 function clone (obj ){

02 var o, obj;

03 if (obj. constructor = Object ){

04 o = new obj. constructor ();

05} else {

06 o = new obj. constructor (obj. valueOf ());

07}

08 for (var key in obj ){

09 if (o [key]! = Obj [key]) {

10 if (typeof (obj [key]) = object ){

11 o [key] = clone (obj [key]);

12} else {

13 o [key] = obj [key];

14}

15}

16}

17 o. toString = obj. toString;

18 o. valueOf = obj. valueOf;

19 return o;

20}

Method 3

View sourceprint? 01 function clone (obj ){

02 function Fn (){}

03 Fn. prototype = obj;

04 var o = new Fn ();

05 for (var a in o ){

06 if (typeof o [a] = "object "){

07 o [a] = clone (o [a]);

08}

09}

10 return o;

11}