var obj1 = {
'name' : 'zhangsan',
'age' : '18',
'language' : [1,[2,3],[4,5]],
};
var obj2 = obj1;
var obj3 = shallowCopy(obj1);
function shallowCopy(src) {
var dst = {};
for (var prop in src) {
if (src.hasOwnProperty(prop)) {
dst[prop] = src[prop];
}
}
return dst;
}
obj2.name = "lisi";
obj2['zzz'] = "zzz";
obj3.age = "20";
obj2.language[1] = ["二","三"];
obj3.language[2] = ["6","五"];
obj3['xxx'] =1;
console.log(obj1);
console.log(obj2);
console.log(obj3);
var a='xxxxx';
var n = a;
a = 'v';
console.log(a);
console.log(n);
var a = [1,2];
var n = a;
a[0] = 3;
n[1] = 4;
console.log(a);
console.log(n);
var a = 100;
var b = a;
a++;
console.log(a);
console.log(b);
function shallowCopy(obj){
var newObj = {};
for(var key in obj){
if(obj.hasOwnProperty(key)){
newObj[key] = obj[key];
}
}
return newObj;
}
var obj1 = {
xxx:[1,2,3],
name:'test'
}
var obj2 = {
xxx:[1,2,3],
name:'test'
}
console.log(55555555555);
console.log(typeof obj1);
console.log(typeof obj2);
if(obj1 == obj2){
console.log('55555555555');
}else{
console.log("666666666");
}
var obj2 = shallowCopy(obj1);
obj2.name = 1;
obj2.xxx[0] = 2;
console.log(obj1);
console.log(obj2);
obj1.xxx[2] = 2;
console.log(obj1);
console.log(obj2);
//深拷貝
function deepCopy(obj){
var objArray = Array.isArray(obj) ? []: {};
if(obj && typeof obj === "object"){
for(var key in obj){
if(obj.hasOwnProperty(key)){
if(obj[key] && typeof obj[key] === "object"){
objArray[key] = deepCopy(obj[key]);
}else{
objArray[key] = obj[key];
}
}
}
}
return objArray;
}
var obj3 = deepCopy(obj1);
console.log(obj3);
console.log(obj1);
obj3.xxx[3] = 1111111;
console.log(obj3.xxx);
console.log(obj1.xxx);
//return 新數組 分配不同內存地址
function testarr(){
return [1,[2,3]];
}
var a = testarr();
var b = testarr();
a[0] = 3;
a[1][0] = 3;
console.log(a);
console.log(b);
// retun 還是引用,共用地址
function newArr(obj){
var newObj = obj;
return newObj;
}
var c = [1,[2,3]]
var a = newArr(c);
var b =newArr(c);
c[0] = 666
a[1][1] =555;
console.log(a);
console.log(b);
潛拷貝,深拷貝
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平臺聲明:文章內容(如有圖片或視頻亦包括在內)由作者上傳并發布,文章內容僅代表作者本人觀點,簡書系信息發布平臺,僅提供信息存儲服務。
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