JavaScript面向对象基础
一, 对象的基本操作
1. 创建对象
// 创建空白对象 var obj1 = {}; var obj2 = new Object(); // 创建包含初始值的对象 var person = { "Name": "Terry", "age": 27, "sex:": "male" }; alert(person.Name); // Terry alert(person.sex); // male
2. 对象访问
下面代码显示访问对象属性的两种方法
var person = {}; person.name = "Terry"; person["age"] = 27; alert(person.name + " " + person.age); var nameList = { name1: "n1", "name2": "n2", name3: "n3" }; var strName; // 访问nameList中的值-1 for (var name in nameList) { strName += nameList[name] + " "; } alert(strName); strName = ""; // 访问nameList中的值-2 for (var i = 0; i < 3; i++) { strName += nameList["name" + (i + 1)]; }
3. delete可以删除某对象中的属性;判断某属性是否存在在一个对象可以用in操作符var nameList = { name1: "n1", "name2": "n2", name3: "n3" }; alert(nameList.name1); // n1 delete nameList.name1; alert("name1" in nameList); // false
3. constructor属性-对应对象初始化时的构造函数
var date = new Date(); alert(date.constructor); // Date alert(date.constructor == Date);// true