我不久前为此创建了一个小object.watch垫片。它适用于IE8，Safari，Chrome，Firefox，Opera等。
// object.watchif (!Object.prototype.watch) Object.prototype.watch = function (prop, handler) { var oldval = this[prop], newval = oldval, getter = function () { return newval; }, setter = function (val) { oldval = newval; return newval = handler.call(this, prop, oldval, val); }; if (delete this[prop]) { // can't watch constants if (Object.defineProperty) // ECMAscript 5 Object.defineProperty(this, prop, { get: getter, set: setter }); else if (Object.prototype.__defineGetter__ && Object.prototype.__defineSetter__) { // legacy Object.prototype.__defineGetter__.call(this, prop, getter); Object.prototype.__defineSetter__.call(this, prop, setter); } } };// object.unwatchif (!Object.prototype.unwatch) Object.prototype.unwatch = function (prop) { var val = this[prop]; delete this[prop]; // remove accessors this[prop] = val; };
