对象的创建方式包括 以下3种：(new Object(),new 构造函数的形式 , Object.create(properties),)
"use strict"
// 方式1
var person = new Object()
person["name"]="jimmy"
console.log(person.name)
person.age=20
console.log(person.age)
console.log(person)
var myCar = new Object()
var propertyName = "make";
myCar[propertyName] = "Ford";
var propertyName1 = "year"
myCar[propertyName1]=1990
console.log(myCar.make)
console.log(myCar.year)
// 方式2
//构造函数
function Car(){
this.make = "Ford"
this.model = "F123"
}
var obj = new Car()
console.log(obj.make)
console.log(obj.model)
// 方式3 Object.create
var roles = {
type:"Admin",//Default value of properties
displayType:function(){
console.log(this.type);//Mehtod which will display type of role
}
}
var super_role = Object.create(roles);
super_role.displayType();
var guest_role = Object.create(roles);
guest_role.type = "Guest";
guest_role.displayType();
var testObj = Object.create(null)
testObj.type = "xx"
testObj.displayType = new Function("a","console.log(a)");
testObj.displayType("abc")
//object assign
var det = {name:"Tom",ID:"E1001"};
// 初始化对象并且给默认值
var copy = Object.assign({},det);
console.log(copy);
for(let val in copy){
console.log(copy[val]);
}
//
var properties = {
name: "john",
ID :"E1002",
age: 28
};
var jo = Object.create(properties);
console.log(jo.name);
console.log(jo.ID);
var john = Object.assign(properties);
console.log(john);
var john1 = Object.assign(john,det);
console.log(john1);
//合并对象,合并对象时大对象没有做拷贝的操作，而是直接引用了对象的指针
var o1 = {a:10};
var o2 = {b:20};
var o3 = {c:30};
// 将值合并到o1 并且返回o1 , 返回值就是被合并的对象
var obj = Object.assign(o1,o2,o3);
console.log(obj);
console.log(o1);
if(o1 === obj){
console.log("o1 is the same as the obj");
}else{
console.log("o1 is different from obj");
}
// o2的值没有改变
console.log(o2);
var o1 = {a:10};
var obj = Object.assign(o1);
obj.a++;
console.log("Value of 'a' in the Merged object after increment");
console.log(obj.a);
console.log("Value of 'a' in the Original Object after increment");
console.log(o1.a);
// delete properties 删除对象中的属性
var myobj = new Object;
myobj.a = 5;
myobj.b = 12;
console.log("before deleting the myobj value is :");
console.log(myobj);
delete myobj.a
console.log("after deleting the myobj value is :");
console.log(myobj);
//比较
var val1 = {name:"Tom"};
var val2 = {name:"Tom"};
console.log(val1 == val2)//return false
console.log(val1 === val2)//return false
var val1 = {name:"Tom"};
var val2 = val1;
console.log(val1 == val2);
console.log(val1 === val2);
var emp = {name:'John',Id:3}
var {name,Id} = emp
console.log(name)
console.log(Id)