Javascript 物件導向式程式設計基礎講解

var userObject = new Object();
userObject.lastLoginTime = new Date();
alert(userObject.lastLoginTime);    

var userObject = {}; // equivalent to new Object()
userObject[「lastLoginTime」] = new Date();
alert(userObject[「lastLoginTime」]);

var userObject = { 「lastLoginTime」: new Date() };
alert(userObject.lastLoginTime);

function func(x) {
    alert(x);
}
func(「blah」);

var func = function(x) {
    alert(x);
};
func(「blah2」);

var func = new Function(「x」, 「alert(x);」);
func(「blah3」);

function sayHi(x) {
    alert(「Hi, 「 + x + 「!」);
}
sayHi.text = 「Hello World!」;
sayHi[「text2」] = 「Hello World... again.」;

alert(sayHi[「text」]); // displays 「Hello World!」
alert(sayHi.text2); // displays 「Hello World... again.」

var myDog = {
    「name」 : 「Spot」,
    「bark」 : function() { alert(「Woof!」); },
    「displayFullName」 : function() {
        alert(this.name + 「 The Alpha Dog」);
    },
    「chaseMrPostman」 : function() { 
        // implementation beyond the scope of this article 
    }    
};
myDog.displayFullName(); 
myDog.bark(); // Woof!

alert(「NaN is NaN: 「 + isNaN(NaN));

function x() {
    this.isNaN = function() { 
        return 「not anymore!」;
    };
}
// alert!!! trampling the Global object!!!
x();

alert(「NaN is NaN: 「 + isNaN(NaN));

Dog spot = new Dog();

function DogConstructor(name) {
    this.name = name;
    this.respondTo = function(name) {
        if(this.name == name) {
            alert(「Woof」);        
        }
    };
}

var spot = new DogConstructor(「Spot」);
spot.respondTo(「Rover」); // nope
spot.respondTo(「Spot」); // yeah!

var spot = new DogConstructor(「Spot」);

// create an empty object
var spot = {}; 
// call the function as a method of the empty object
DogConstructor.call(spot, 「Spot」);

// Think of this as class Dog
function Dog(name) {
    // instance variable 
    this.name = name;
    // instance method? Hmmm...
    this.respondTo = function(name) {
        if(this.name == name) {
            alert(「Woof」);        
        }
    };
}

var spot = new Dog(「Spot」);

function respondTo() {
    // respondTo definition
}

function Dog(name) {
    this.name = name;
    // attached this function as a method of the object
    this.respondTo = respondTo;
}

var buddy = new Dog(「Buddy「);

Dog.prototype = new Object();

    function DateTime() { }

    // set static method now()
    DateTime.now = function() {
        return new Date();
    };

    alert(DateTime.now());

var greaterThan300 = filter(
    function(x) { return (x > 300) ? true : false; }, 
    someRandomNumbers);

function makeGreaterThanPredicate(lowerBound) {
    return function(numberToCheck) {
        return (numberToCheck > lowerBound) ? true : false;
    };
}

var greaterThan10 = makeGreaterThanPredicate(10);
var greaterThan100 = makeGreaterThanPredicate(100);
alert(filter(greaterThan10, someRandomNumbers));
alert(filter(greaterThan100, someRandomNumbers));

function Person(name, age) {
    this.getName = function() { return name; };
    this.setName = function(newName) { name = newName; };
    this.getAge = function() { return age; };
    this.setAge = function(newAge) { age = newAge; };
}

var ray = new Person(「Ray」, 31);
alert(ray.getName());
alert(ray.getAge());
ray.setName(「Younger Ray」);
// Instant rejuvenation!
ray.setAge(22);
alert(ray.getName() + 「 is now 「 + ray.getAge() + 
      「 years old.」);

function Person(name, age) {
    var occupation;
    this.getOccupation = function() { return occupation; };
    this.setOccupation = function(newOcc) { occupation = 
                         newOcc; };
  
    // accessors for name and age    
}

Person.prototype.somePublicMethod = function() {
    // doesn』t work!
    // alert(this.name);
    // this one below works
    alert(this.getName());
};

// class Pet
function Pet(name) {
    this.getName = function() { return name; };
    this.setName = function(newName) { name = newName; };
}

Pet.prototype.toString = function() {
    return 「This pet』s name is: 「 + this.getName();
};
// end of class Pet

var parrotty = new Pet(「Parrotty the Parrot」);
alert(parrotty);

var MSDNMagNS = {};

MSDNMagNS.Pet = function(name) { // code here };
MSDNMagNS.Pet.prototype.toString = function() { // code };

var pet = new MSDNMagNS.Pet(「Yammer」);

var MSDNMagNS = {};
// nested namespace 「Examples」
MSDNMagNS.Examples = {}; 

MSDNMagNS.Examples.Pet = function(name) { // code };
MSDNMagNS.Examples.Pet.prototype.toString = function() { // code };

var pet = new MSDNMagNS.Examples.Pet(「Yammer」);

// MSDNMagNS.Examples and Pet definition...

// think 「using Eg = MSDNMagNS.Examples;」 
var Eg = MSDNMagNS.Examples;
var pet = new Eg.Pet(「Yammer」);
alert(pet);

    function object(o) {
        function F() {}
        F.prototype = o;
        return new F();
    }