模拟windows平台的上下文菜单效果代码

  代码演示:

  

   [Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]

  结构:

  

复制代码 代码如下:

  <div id="wrap">

  <ul id="menu">

  <li><a href="">撤销</a></li>

  <li><a href="">重做</a></li>

  <li><a href="">复制</a></li>

  <li><a href="">粘贴</a></li>

  <li><a href="">大小写转换</a></li>

  <li><a href="">回车</a></li>

  <li><a href="">拼写检查</a></li>

  <li><a href="">新建</a></li>

  <li><a href="">自定义</a></li>

  <li><a href="">图形选项</a></li>

  <li class="no"><a href="">关闭</a></li>

  </ul>

  </div>

  code是这样:

  

复制代码 代码如下:

  function $(id) {

  return document.getElementById(id);

  };

  var EventUnit = {

  addHandler: function(element, type, handler) {//添加事件处理程序

  if(element.addEventListener) {

  element.addEventListener(type, handler, false);

  } else if(element.attachEvent) {

  element.attachEvent('on' + type, handler);

  } else {

  element['on' + type] = handler;

  };

  },

  getEvent: function(event) {

  return event ? event : window.event;

  },

  preventDefault: function(event) {//取消事件默认动作

  if(event.preventDefault) {

  event.preventDefault();

  } else {

  event.returnValue = false;

  };

  }

  }

  EventUnit.addHandler(window, 'load', function() {

  var wrap = $('wrap');

  var menu = $('menu');

  var menuStyle = menu.style.display;

  var x = wrap.offsetLeft + wrap.clientWidth, y = wrap.offsetTop + wrap.clientHeight;

  var w = 0, h = 0;

  var left = 0, top = 0;

  EventUnit.addHandler(wrap, 'contextmenu', function(event) {

  event = EventUnit.getEvent(event);

  EventUnit.preventDefault(event);

  menu.style.display = 'block';

  w = menu.clientWidth;

  h = menu.clientHeight;

  left = (x - event.clientX >= w) ? event.clientX - wrap.offsetLeft : event.clientX - wrap.offsetLeft - w;

  top = (event.clientY + h <= y) ? event.clientY - wrap.offsetTop : event.clientY - wrap.offsetTop - h;

  menu.style.left = left + 'px';

  menu.style.top = top + 'px';

  });

  EventUnit.addHandler(document, 'click', function() {

  menu.style.display = menuStyle;

  });

  });