JavaScript -- 面向对象的简单分析

// 第一种：直接赋值：
//var person = {
//    name:"iwen",
//    age:"30",
//    eat:function(){
//        alert("能吃")
//    }
//}
//alert(person.name);

// 使用原型为对象赋值
function Person(){

}
Person.prototype = {
name:"iwen",
age:"30",
eat:function(){
alert("我在吃")
}
}

var p = new Person();
alert(p.eat);

//------------第二类--------------//
// 对象之间的调用
/*
function People(name){
this._name = name;

}
People.prototype.say = function(){
alert("hello,"+this._name);
}

function Student(name){
this.name = name;
}

Student.prototype = new People("iwen");

var superSay = Student.prototype.say;

Student.prototype.say = function(){
superSay.call(this);
alert("stu-hello");
}

var s = new Student("iwen");
s.say()
*/

//------ 上述可以改写为:（将对象属性封装为私有属性）
(function(){
var n = "ime"
function People(name){
this._name = name;
}
People.prototype.say = function(){
alert("peo-hello,"+this._name+n);
}
window.People = People;   // 如果想让外界使用,就让他赋给window
}());

(function(){
function Student(name){
this._name = name;
}
Student.prototype = new People();
var superSay = Student.prototype.say;
Student.prototype.say = function(){
superSay.call(this);
alert("stu-hello,"+this._name);
}
window.Student = Student;
}());
var s = new Student("iwen");
s.say()

// ------------第三类--------------- //

/*
// 无参数的赋值
//  全部通过对象赋值的操作
function Person(){
var _this = {}
_this.sayHello = function(){
alert("hello");
}
return _this;
}

function Teacher(){
var _this = Person();
var superSay = _this.sayHello();
_this.sayHello = function(){
alert("Thello");
}
return _this;
}

var t = Teacher();
t.sayHello();
*/

//-------以上是无参数,下面是有参数类型的------//

// 写完后,可以尝试将第一个函数块封装起来,对比一下使用区别
(function(){
var n = "Tom";
function Person(name){
var _this = {}
_this._name = name;
_this.sayHello = function(){
alert("hello,"+this._name+  n);
}
return _this;
}
window.Person = Person;
}())

function Teacher(name){
var _this = Person(name);
var superSay = _this.sayHello();
_this.sayHello = function(){
alert("Thello"+this._name);
}
return _this;
}

var t = Teacher("iwen");
t.sayHello();