台灣數位學習數位教學平台 RSS feed provider zh-tw http://lms.xms.com.tw/board.php?courseID=100&f=doclist&folderID=1015 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=8636 this 一般會指向 global，因此如果是物件，要特別小心要用 newfunction obj() {  this.value = "v";}var o = obj();      // 錯誤，this 指向 global, browser 中通常是 windowvar o = new obj();  // this 指向物件解決方法 ~ 自我呼叫的建構式function obj() {  if (!(this instanceof obj)) {    return new obj();  }  this.value = "v";} Wed, 06 Jun 2012 12:15:12 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4330 Object.prototype.implements = function(funcName) {   return this && this[funcName] && this[funcName] instanceof Function; }   function isShape(obj) {   return obj.implements("getArea");  // 檢查是否 implement getArea() 的介面  }   function addAreas(s1, s2) {   if (isShape(s1) && isShape(s2))     return s1.getArea() + s2.getArea(); } Sat, 05 Feb 2011 21:32:23 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4329 instanceof   explore attributes & functions function obj() {   this.color = "red";   this.flavor = "strawberry";   this.func = function() {}; }   var o = new obj(); for (var i in o)   console.log(o[i]); Sat, 05 Feb 2011 21:22:06 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4328 // 盡量不要擴充內建型別的原型，缺點主要是難以維護，尤其別人使用時Array.prototype.indexOf = function(obj) {   var ret = -1;   for (var i=0; i<this.length; i++)     if (this[i] == obj) { ret = i; break; }   return ret; }   Array.prototype.contains = function(obj) {   return (this.indexOf(obj) >= 0); }   Array.prototype.append = function(obj, nodup) {   nodup = nodup || false;  // default   if (this.contains(obj) && nodup) return;   this[this.length] = obj; }   var num = [1, 2, 3, 4, 5]; num.append(6); Sat, 05 Feb 2011 20:37:53 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4327 // object constructor functionfunction obj(name, size) {   this.name = name;   this.size = size; }   obj.prototype.tellSize = function() { return this.size; } var o1 = new obj();            // no color obj.prototype.color = "blue"; var o2 = new obj();            // has color Sat, 05 Feb 2011 20:28:34 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4326 http://www.dotblogs.com.tw/cloudio/archive/2008/09/26/5487.aspx    var animal = function() {  this.eat = function()  { alert("animal eat"); }  this.walk = function() { alert("animal walk"); }}   var dog = function() {  this.play = function() { alert("dog play"); }  this.walk = function() { alert("dog walk"); } }   dog.prototype = new animal;   var bill = new dog();bill.play();bill.eat();bill.walk(); Sat, 05 Feb 2011 16:18:04 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4325 JSON (Javascript Object Notation) var obj = {                      // object {}   key1: "v1",                    // key: value   "key 2": "v2",                 // "k e y": value   ary: [1, 2, 3],                // array []   aryObj: [     {name: "su", age: 10},     {name: "liu", age: 12}   ],   date: new Date(1605, 11, 05),  // evaluated dynamically   sum: function(val) {           // define a method     return val + this.key1;   } } Sat, 05 Feb 2011 12:08:47 +0800 http://lms.xms.com.tw/board.php?courseID=100&f=doc&cid=4324 Associated array   var obj = new Object();  // create obj.size = 12;           // attribute, dynamically obj['size'] = 12;        // equivalent to obj.size, associated array  obj.show = function() {  // method   alert(this.size); }   function foo() { ... } obj.show = foo;    // pre-defined function Sat, 05 Feb 2011 12:06:08 +0800