面向对象
JavaScript的继承机制
代码示例：
<script>
//prototype
function Person(name ,age){
this.name = name;
this.age = age;
this.info = function (){
document.write("姓名："+this.name+"<br>");
document.write("年龄："+this.age+"<br>");
}
}
var p1 = new Person("法外狂徒张三",29);
p1.info();
Person.prototype.walk = function(){
document.write(this.name+"溜达"+"<br>");
}
document.writeln("<hr>");
var p2 = new Person("leegang" , 30);
p2.info();
document.writeln("<hr>");
p2.walk();
p1.walk();
</script>
构造器实现伪继承
使用apply或者call实现伪继承
代码示例：
<script>
//prototype
function Person(name ,age){
this.name = name;
this.age = age;
}
Person.prototype.sayHello = function(){
console.log(this.name+"正在打招呼");
}
var p1 = new Person("法外狂徒张三",29);
p1.sayHello();
function student(name,age,grade){
Person.call(this,name,age);
this.grade = grade;
}
student.prototype = new Person();
student.prototype.intro = function(){
console.log("%s是个学生，读%d年级",this.name,this.grade);
}
var stu = new student('李四',34,5);
var stu2 = new student('王五',33,4);
console.log(stu instanceof student);
console.log(stu instanceof Person);
stu.intro();
stu2.intro();
stu.sayHello();
stu2.sayHello();
</script>
使用call方法继承构造方法，使用prototype属性来继承类的其他方法。
继承代码示例：
script>
function Animal (sex,age){
this.sex = sex;
this.age = age;
}
Animal.prototype.intro = function(){
console.log("性别："+this.sex+",年龄："+this.age);
}
function Dog(kind,sex,age){
this.kind = kind;
Animal.call(this,sex,age);
}
Dog.prototype = new Animal();
Dog.prototype.voice = function (){
console.log(this.kind+"叫的声音是：汪汪汪");
}
function Cat(kind,sex,age){
this.kind = kind;
Animal.call(this,sex,age);
}
Cat.prototype = new Animal();
Cat.prototype.voice = function (){
console.log(this.kind+"叫的声音是：嗷嗷嗷");
}
var d = new Dog("哈士奇","公",12);
d.intro();
d.voice();
var c = new Cat("波斯猫","母",5);
c.intro();
c.voice();
</script>
创建对象
