Looking for ways to deep copy objects that contain nested and circular structures, neither of these ( 1 , 2 , 3 , 4 ) had the perfect solution when it comes to circular references and prototypal inheritance.
I've written my own implementation here. Does it do the job well or count as a better solution?
/*
a function for deep cloning objects that contains other nested objects and circular structures.
objects are stored in a 3D array, according to their length (number of properties) and their depth in the original object.
index (z)
|
|
|
|
|
| depth (x)
|_ _ _ _ _ _ _ _ _ _ _ _
/_/_/_/_/_/_/_/_/_/
/_/_/_/_/_/_/_/_/_/
/_/_/_/_/_/_/...../
/................./
/..... /
/ /
/------------------
object length (y) /
*/
function deepClone(obj) {
var i = -1, //depth of the current object relative to the passed 'obj'
j = 0; //number of the object's properties
var arr = new Array(); //3D array to store the references to objects
return clone(obj, arr, i, j);
}
function clone(obj, arr, i ,j){
if (typeof obj !== "object") {
return obj;
}
var result = Object.create(Object.getPrototypeOf(obj)); //inherit the prototype of the original object
if(result instanceof Array){
result.length = Object.keys(obj).length;
}
i++; //depth is increased because we entered an object here
j = Object.keys(obj).length; //native method to get the number of properties in 'obj'
arr[i] = new Array(); //this is the x-axis, each index here is the depth
arr[i][j] = new Array(); //this is the y-axis, each index is the length of the object (aka number of props)
//start the depth at current and go down, cyclic structures won't form on depths more than the current one
for(var depth = i; depth >= 0; depth--){
//loop only if the array at this depth and length already have elements
if(arr[depth][j]){
for(var index = 0; index < arr[depth][j].length; index++){
if(obj === arr[depth][j][index]){
return obj;
}
}
}
}
arr[i][j].push(obj); //store the object in the array at the current depth and length
for (var prop in obj) {
result[prop] = clone(obj[prop], arr, i, j);
}
return result;
}
Can you try the below simple logic. Convert js object into new String and again convert as object.
Eg:
var car = {type:"Fiat", model:"500", color:"white"};
var cloneStr = new String(JSON.stringify(car));
var carClone = JSON.parse(cloneStr);
carClone.type = "Maruthi";
alert(JSON.stringify(car)) ;
alert(JSON.stringify(carClone)) ;
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