自定义右键菜单

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>自定义右键菜单</title>
    <style>
        div{ 400px;height: 400px;background:cyan;}
        ul{ 80px;height: 100px;background: orange;position:absolute;display:none;}
    </style>
    <script>
        window.onload =function(){
            //阻止系统自带右键菜单
            document.oncontextmenu = function(){
                return false;
            }
            //自定义右键菜单
            var oDiv = document.getElementById('div');
            var oUl = document.getElementById('menu');
            oDiv.onmousedown = function(ev){
                //获取事件对象
                var e = ev || window.event;
                //判断按下的是否为右键
                if(e.button == 2){
                    oUl.style.display = 'block';
                    oUl.style.left = e.clientX+'px';
                    oUl.style.top = e.clientY+'px';
                }else{//点击别的键时关闭自定义菜单
                    oUl.style.display = 'none';
                }
            }

        }

    </script>
</head>
<body>
    <div id="div"></div>
    <ul id="menu">
        <li>选项1</li>
        <li>选项2</li>
        <li>选项3</li>
    </ul>
</body>
</html>
浏览器效果