Javascript面向对象编程

//define class
var Person = function (name, age){
    var _slef = this;

    //private property
    _slef.name = name;
    _slef.age = age;

    if (typeof Person._initialized == 'undefined') {

        //private method
        Person.prototype._eat = function () {
            console.log('eat....');
        }

        //public method
        Person.prototype.sayHello = function () {
            var msg = [];
            msg.push('welcome，');
            msg.push(_slef._name);
            console.log(msg.join(''));
        }

        Person._initialized = true;
    }

    //static public method
    Person.sleep = function () {
        console.log('sleep...');
    }
}

var Student = function (name,age, number) {
    var _slef = this;
    Person.call(_slef,name,age);
    _slef._number = number;

    if (typeof Student._initialized == 'undefined') {

        Student.prototype.sayNumber = function () {
            var msg = [];
            msg.push('my name is ');
            msg.push(_slef.name);
            msg.push(',my number is ');
            msg.push(_slef._number);
            console.log(msg.join(''));
        }
        Student._initialized = true;
    }
}

Student.prototype = new Person();

var person = new Person('yywang', 21);
person.sayHello();
Person.sleep();
var student = new Student('yywang', 12, '2011');
console.dir(student);
student.sayNumber();
student.sayHello();

参考：http://w3school.com.cn/js/pro_js_object_defining.asp

       http://w3school.com.cn/js/pro_js_inheritance_implementing.asp