js Proxy

w={"navigator":"hehe"}
 var handler = {
    get(target, key,receiver){
      console.log("target",target,receiver);
      return Reflect.has(target, key)
        ? Reflect.get(target, key)
        : undefined
    },
    set(target, key, value){
      return Reflect.set(target, key, value);
    }
  }

w["name"]="zhangsan"
w = new Proxy(w, handler);
console.log(w.name)