DIV CSS 佈局教程網

檢查屬性

var mouse = {
 "name": "betta",
 "age": 3,
 "varieties": "milaoshu"
}
 
mouse.hasOwnProperty("name"); // true
mouse.hasOwnProperty("sex"); //false

增加屬性

定義個對象 dog，然後賦予各種特性，再賦予 color特性，最後遍歷所有的屬性以及值

var dog={
 name:"芒果",
 type:"會之王",
 eat:function(){
  alert("吃");
 }
}
 Object.prototype.color="白色";
 var name;
 for(name in dog){
  document.write(name+" "+dog[name]+"<br>")
 }

效果如下

name 芒果
type 會之王
eat function (){ alert("吃"); }
color 白色

刪除屬性

var cat = {
  "name": "tom",
  "sex": "man",
  "color": "yellow"
}
delete cat.name;
cat.sex = undefined;
cat.color = null;
alert("name屬性是否存在：" + cat.hasOwnProperty("name")); //false
alert("sex屬性是否存在：" + cat.hasOwnProperty("sex")); //true
alert("color屬性是否存在：" + cat.hasOwnProperty("color")); //true

訪問屬性

var cat = {
  "name": "tom",
  "sex": "man",
  "color": "yellow"
}
var name1 = cat.name; //通過點操作符來訪問對象屬性
var name2 = cat["name"]; //通過中括號操作符來訪問對象屬性

還有創建對象的兩種方式

var obj = new Object();
obj.name = "MangGuo";
obj.age = 25;

var obj = {
  name : "MangGuo", //name是屬性名，"MangGuo"是值
  age : 25
}