我们的vue3 使用proxy 来代替vue2 的 Object.defineProperty 
效率更高，值得我们学习

  <script>
        var target = {
            name: "xiaoming",
            age: 18
        }
        // handler 是一个对象
        const handler = {
            set(target, prop, value) {
                let result = Reflect.set(target, prop, value)
                console.log("设置的操作" + result)
                return true;
            },
            get(target, value) {
                let result = Reflect.get(target, value)
                console.log("获取的的操作" + result)
            }
        }
        let proxy = new Proxy(target, handler);
        proxy.coure = "java"
        console.log(proxy)
    </script>