我希望扩展对象和数组类,以便在构造后能够听取对其实例所做的任何更改。如何侦听动态添加的对象字段中的更改?
最好的我现在能做的就是添加自定义获取和设置功能在初始化/建筑实例的给定字段:
var myObj = new CustomObject({name:'foo'});
myObj.name = 'bar'; // this will log "'name' in 'myObj' updated:'bar'"
//however:
myObj.age = 85; // this mutation will slip by unnoticed,
// since the 'age' field was never specified
// at initialization meaning no custom set/get
// functions where attached.
有没有一种方式来实现以下功能?
var myObj = new CustomObject();
myObj.name = 'foo';// this should log something like:
// "A new field 'name' was created for myObj with value 'foo'"
注:我正在寻找不涉及投票的解决方案。
现在我已经(导致第一代码块所示的功能)什么:
function CustomObject(data) {
var that = this;
for(var field in data){
prepField(field);
}
function prepField(field){
Object.defineProperty(that, field, {
set: function(val){
data[field] = val;
console.log(field,'in',that,'updated:',val);
},
get: function(){
console.log(field,'in',that,'requested');
return data[field];
},
enumerable:true
});
}
return this;
}
提前感谢!
所以你想看任何*属性? – 2012-04-13 17:33:27
是的,而不是侦听预定义的字段集我宁愿听正在调用的函数来创建新字段,并设置它们的值,当我说myObj.randomfieldname = somevalue; – Marcus 2012-04-15 10:22:14
好吧,我想你已经知道了,但让我只是说,地狱里没有办法让你获得像这样的工作,并有适当的浏览器支持。 – 2012-04-16 04:28:52