你可以用getter和setter方法實現這一目標。
var obj = {
get foo() {
console.log({ name: 'foo', object: obj, type: 'get' });
return obj._foo;
},
set bar(val) {
console.log({ name: 'bar', object: obj, type: 'set', oldValue: obj._bar });
return obj._bar = val;
}
};
obj.bar = 2;
// {name: 'baz', object: <obj>, type: 'set', oldValue: undefined}
obj.foo;
// {name: 'foo', object: <obj>, type: 'get'}
或者,在支持代理的瀏覽器中,您可以編寫更通用的解決方案。
var obj = {
foo: 1,
bar: 2
};
var proxied = new Proxy(obj, {
get: function(target, prop) {
console.log({ type: 'get', target, prop });
return Reflect.get(target, prop);
},
set: function(target, prop, value) {
console.log({ type: 'set', target, prop, value });
return Reflect.set(target, prop, value);
}
});
proxied.bar = 2;
// {type: 'set', target: <obj>, prop: 'bar', value: 2}
proxied.foo;
// {type: 'get', target: <obj>, prop: 'bar'}
'Proxy()'現在有! – Jai
[Proxy](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Proxy) –
或者使用[getter](https://developer.mozilla.org/en/docs/ Web/JavaScript/Reference/Functions/get)或[setter](https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Functions/set) –