border: 1px solid #cccccc;
<div contextmenu="mymenu">
<p>用鼠标右键单击黄色框区域查看上下文菜单</p>
<menu type="context" id="mymenu" onshow="myFunction()">
<menuitem label="Refresh" onclick="window.location.reload();" icon="ico_reload.png"></menuitem>
<menuitem label="Twitter" icon="ico_twitter.png" onclick="window.open('//twitter.com/intent/tweet?text=' + window.location.href);"></menuitem> <menuitem label="Facebook" icon="ico_facebook.png" onclick="window.open('//facebook.com/sharer/sharer.php?u=' + window.location.href);"></menuitem> <menuitem label="发邮件到该页面" onclick="window.location='mailto:?body='+window.location.href;"></menuitem>
<p><strong>注意：</strong>目前只有 Firefox 浏览器支持 onshow 属性。</p>