Shallow and deep copies in JavaScript

Shallow copy: Copy reference.

Both the new object and the source object after the copy are pointing to the same reference address, so the operation is affected by each other.

Let A = {num:1};

Let B = A;

Console.log (A===B); True

A.num = 2;

Console.log (b.num);//2

Deep copy: Copy data

A new object with a deep copy allocates memory space in memory and creates a new copy of all the data from the source object, referencing a reference to the source object to the same address.

Manual copy: Manually give each property of the source object sequentially to each property of the new object.

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

var. ={a:one,b:one.b,c:one.c};

one.a=10;

Console.log (ONE.A);//10

Console.log (TWO.A)//1

Shallow and deep copies in JavaScript