模拟windows平台的上下文菜单效果代码_javascript技巧

代码演示：

<meta charset="utf-8"> <title>无标题文档</title> <style> <!-- body{background: #222; font: 14px 'Microsoft Yahei', Arial;} ul,li{list-style: none;padding:0;margin:0;} a{text-decoration: none;color:#000;} #wrap { width: 800px; height: 550px; border:1px solid #FF9C00; background: #F0E6AF; position:relative; margin: .5em auto; } #wrap ul { background: #eee; border: 1px solid #999; width: 150px; position: absolute; display: none; -moz-box-shadow: 3px 3px 9px #999; -webkit-box-shadow: 3px 3px 9px #999; -o-box-shadow: 3px 3px 9px #999; box-shadow: 3px 3px 9px #999; } #wrap ul li { border-bottom: 1px solid #ddd; line-height: 24px; } #wrap li.no {border-bottom: none;} #wrap ul li a { display: block; padding-left: .5em; } #wrap ul li a:hover { background-color: #FFBD00; } --> </style> <script type="text/javascript"> //<![CDATA[ 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; }); }); //]]> </script> <div id="wrap"> <p>单击右键看效果~</p> <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>
[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:

• 撤销


• 重做


• 复制


• 粘贴


• 大小写转换


• 回车


• 拼写检查


• 新建


• 自定义


• 图形选项


• 关闭

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 menu.style.left = left + 'px';
menu.style.top = top + 'px';
});

EventUnit.addHandler(document, 'click', function() {
menu.style.display = menuStyle;
});
});