<button id="button">有人想加你為好友</button>
<p id="text"></p>
;(function (){
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        var txt = document.getElementById("text");
        btn.onclick = function (){
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            }
        };
        function popNotice(){
            if(Notification.permission == "granted"){
                var notification = new Notification("你好:",{
                    body:"請(qǐng)問今晚有空嗎",
                    icon:"http://image.zhangxinxu.com/左邊頭像地址"
                });
                notification.onclick = function (){
                    txt.innerHTML = new Date().toTimeString().split(" ")[0]+"收到信息";
                    notification.close();
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})();