js的属性监听

<!DOCTYPE html>

---

<html>

---

<head>

　<meta charset="UTF-8">

    <title></title>

</head>

---

<body>

    <div id="target" style="height: 200px; width: 600px;aqua; display: none;"></div>

    <div id="test" style="position: relative; display: block;" class="show">test</div>

---

    <script type="text/javascript">

        var MutationObserver = window.MutationObserver || window.WebKitMutationObserver || window.MozMutationObserver;

        var element = document.querySelector('#test');

        var target = document.querySelector('#target')

        var observer = new MutationObserver(function (mutations) {

            mutations.forEach(function (mutation) {

                if (mutation.type == "attributes" ) {

                    console.log(mutation.target.style.display);

                    if(mutation.target.style.display == 'none'){

                        testing.style.display = 'none'

                    }else{

                        testing.style.display = 'block'

                    }

                }

            });

        });

        observer.observe(element, {

            attributes: true 

        });

    </script>

---

</body>

</html>