檢查屬性
var mouse = { "name": "betta", "age": 3, "varieties": "milaoshu"} mouse.hasOwnProperty("name"); // truemouse.hasOwnProperty("sex"); //false增加屬性
定義個對象 dog，然后賦予各種特性，再賦予 color特性，最后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")); //falsealert("sex屬性是否存在：" + cat.hasOwnProperty("sex")); //truealert("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}新聞熱點
疑難解答
