Object关于属性property的静态方法

Object.defineProperty

Object.defineProperty(obj, prop, {
value: undefined,
enumerable: true,
writable:true,
get: function() {return value},
set: function(newValue) {value = newValue;}
})
当时配置了set和get时，则不能配置value。

Object.getOwnPropertyNames

Object.getOwnPropertyNames(obj)

Object.getOwnPropertyDescriptor

Object.getOwnPropertyDescriptor(obj, prop)

Object.hasOwnProperty(obj, prop)