"use strict";
// *****************************************************************
// 操作数据属性
var person = {name: 'hugh',age: 29,sayName: function() { console.log(1); }
}
// 修改属性默认特性:Object.defineProperty()
Object.defineProperty(person, "name", {writable: true,value: 'dong',configurable: false,enumerable: false
});
console.log(person);// *****************************************************************
// 操作访问器属性
var book = {_year: 2004, // _作为标记只能通过对象访问的属性edition: 0
};
Object.defineProperty(book, "year", {// 访问器属性year包含setter和getter函数get: function() {return this._year;},set: function(newValue) {this._year = newValue;this.edition = newValue - 2004;}
})
book.year = 2008;
console.log(book);
console.log(book.edition);
// 旧方法,ie8部分不支持defineProperty()
// 严格模式不可用
// book._defineGetter_("year",function(){//     return this._year;
// });
// book._defineSetter_("year",function(newValue){//     this._year = newValue;
//     this.edition = newValue - 2014;
// });// *****************************************************************
// 定义多个属性
var book2 = {};
Object.defineProperties(book2, {// 数据属性
    _year: {value: 2004,writable: false,enumerable: false,configurable: true},edition: {value: 0,writable: false,enumerable: false,configurable: true},// 访问器属性
    year: {get: function() {return this._year;},set: function(newValue) {this._year = newValue;this.edition = newValue - 3000;}}
});
console.log(book2);// *****************************************************************
// 查看属性的属性
console.log(Object.getOwnPropertyDescriptor(book2,'_year'));
console.log(Object.getOwnPropertyDescriptor(book2,'edition'));
console.log(Object.getOwnPropertyDescriptor(book2,'year'));