1.var lists=[{name: "Jiali", Age:28},{name: "Jia", age:30},{name: "Ki", age:30}];
var listcopy=json.parse (json.stringify (lists));
Listscopy[1]= "AAA";
listscopy;//Index 1 Changed {name: "AAA", age:30}
lists//
2.var Arr=[{x:1,y:3,z:r},{a:3,b:5,c:6},{1:6,m:8,n:9}];
Arr.foreach (function (item,index) {
For (i in Item) {
if (i== "x" {
Console.log ("1");
else{
Console.log ("2")}
}}
})
The second method:
Arr.foreach (function (item,index) {
if (Item.hasownproperty ("x")) {
Consle.log ("1");
})
3 The focus is on prototypes.
3.1
function person () {}//-Empty functions Object
Person.prototype.name= "Jiai";
person.prototype.age=20;
var person1=new person ();
var person2=new person ();
Person1.name;
3.2
var cat={};//create an empty object
Cat.name= "Jiaji";
Cat.color= "Blue";
var cat1={};
Cat1.name= "Xiaoh";
Cat1.color= "Hong";
function encapsulation
function Cat (Name,color) {//Common functions
return{
Name:name,
Color:color
}
var cat1=cat ("Xiaoh", "Red");
var cat2=cat ("Jiali", "baise");
Cat1.name;
};
4, the difference between a constructor and a normal function
1, through New
Functon Cat (Name,color) {
This.name=name;
This.color=color;
This.type= "Animal";//This is a public class. This is not optimal.
This.eat=function () {//This is also a public class
Console.log ("Love to Eat Mice");
}
};
cat.prototype.type= "Animals";
Cat.prototype.eat=function () {
Console.log ("Eat Mouse");
}
var cat1=new Cat ("Xiaoming", "yellow");
Cat1.name;
5. Prototype
Prototype in the public class, this is the best
6.prototype Verification
Returns true regardless of its property or prototype property;
The property of Hasownprototype itself is true if the prototype property is returned to False
Console.log ("name" in cat1);//true;
Console.log ("type" in CAT1);//true
Console.log (Cat1.hasownprotype ("name"));//true;
Console.log (Cat1.hasownprotype ("type"));//false;
7. Most importantly, the inheritance of the constructor can form a relationship chain
function Animal () {//Animal object
this.type= "Animals";
};
function Cat (name,color) {
This.name=name;
This.color=color;
};
Apply () One object to another object apply (this, parameter) to the array
Call () is also an object that is tuned to another object one by one
function Cat (name,color) {
Animal.apply (this);//Binds the parent object's constructor to the child object this is equivalent to the parent class, changing the scope
This.name=name;
This.color=color;
};
var cat1=new Cat ("Jia", "yellow")
Console.log (Cat1.type);
。。。 Prototype
function Animal () {//Animal object
this.type= "Animals";
};
Animal.prototype.type= "Animal";//package and plug-in used more
function Cat (name,color) {
This.name=name;
This.color=color;
};
Cat.prototype=new Animal ();
var cat1=new Cat ("Jia", "yellow")
Console.log (Cat1.type);//Animals
The most important thing in JS is: Prototype object Common object and Function object constructor