JavaScript objects
This lesson is to talk:
- JavaScript object creation
- JavaScript Object basic operations
- JavaScript function object
Speaker teachers: Head teacher
A. JavaScript object created
1. Types of objects
1.js like built-in objects such as Number
2. The host environment runs in a browser window document
3. The creation of the object itself
2. Creating objects
1. Create an object, then the object to the new properties and methods.
Box new new Object = var (); // create an Object Object
= box.name 'Lee'; // create and assign a name attribute
= 100 box.age; // create a property and assign age
= function box.run () { // create a run () method returns the value and
return this.name + this.age + 'operation ...';
};
alert (() box.run); value // output attributes and methods
The above creates an object, and create properties and methods, this in the run () method in, the box is to represent the object itself. This method is the most basic JavaScript object is created.
Define and modify the properties of the method
Object.defineProperty (Object, "Properties", "characteristics of the object property")
Object.defineProperty（p,“yy”，{value:100,writeable:false}）;
p.yy
p.yy=200;
p.yy
Add more properties:
object.defineProperties（p,{
abc:{
value:1000,
writeable:false
},
qwe{
value:true
}，
height:{
get:function(){
return :180
},
Set:function(val){
Console.log(val);
}
}
}）
3. Because of the way to create an object above can easily modify object properties, we use get set way to create.
var p = {
name:"Head",
work:function() {
console.log("wording...");
},
_age: 18, // if the property inside the object calling convention of naming is _age
get age(){
this._age return; // GET is used to return
},
Age SET (Val) { // SET is used to set the
if (val<0 || val> 150) {
throw new Error ( "Age is not lawful.")
}else{
this._age = val;
}
}
};
console.log(p.name);
console.log(p.age); console.log(p.name);//输出chen
A direct result of debugging browser:
p.age
"18"
p.age=23
"23"
p.age=200
Uncaught Error: invalid value