利用jQuery的$.event.fix函数统一浏览器event处理
做WEB前端开发的人都知道不同的浏览器对事件的处理方式是有区别的，比如得到触发事件的元素引用在IE浏览器下是：event.srcElement，在FF浏览器下则是：event.target，另外又比如在FF浏览器下得到光标相对页面的位置是event.pageX，而IE浏览器下的处理方式又是不一样的，当然还有一些像“阻止事件冒泡”以及“取消浏览器默认行为”等，不同浏览器也有不同的处理方式，如果我们要使JavaScript在不同的浏览器下能正常处理事件代码，就要分别进行判断处理。现在jQuery为我们提供了统一兼容处理函数$.event.fix(e)，这个函数官方并没有在文档中说明用法，是我在阅读框架代码的时候发现可以这样使用。
一、如何使用
使用jQuery的event兼容处理主要分以下几个简单步骤进行：
1、在网页head区引用jQuery框架库文件；
2、定义一个事件处理方法，在调用的地方统一传入event参数；
3、在事件方法内部首先利用$.event.fix把旧的事件转换成新的事件引用；
4、在事件方法后面使用经过兼容处理后的事件对象方法和属性。
二、使用示例
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>利用jQuery的$.event.fix函数统一浏览器event处理</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js"></script>
</head>
<body>
<input type="button" value="http://blog.csdn.net/webflash" onclick="eventHandler(event)" />
<script type="text/javascript">
//请使用不同浏览器测试本页，你将看到一样的结果
function eventHandler(e)
{
var event = $.event.fix(e);
var elem = event.target;
alert('当前点击对象的标签名是:' + elem.tagName);
alert('当前点击按钮文本是:' + elem.value);
alert('pageX:' + event.pageX + ',pageY:' + event.pageY);
//得到按键码
event.keyCode
//取消浏览器默认行为
event.preventDefault();
//取消事件冒泡
event.stopPropagation();
//...还有好些不是很常用属性，这里不一一列举
}
</script>
</body>
</html>
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<title>利用jQuery的$.event.fix函数统一浏览器event处理</title>
<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.3/jquery.min.js"></script>
</head>
<body>
<input type="button" value="http://blog.csdn.net/webflash" onclick="eventHandler(event)" />
<script type="text/javascript">
//请使用不同浏览器测试本页，你将看到一样的结果
function eventHandler(e)
{
var event = $.event.fix(e);
var elem = event.target;
alert('当前点击对象的标签名是:' + elem.tagName);
alert('当前点击按钮文本是:' + elem.value);
alert('pageX:' + event.pageX + ',pageY:' + event.pageY);
//得到按键码
event.keyCode
//取消浏览器默认行为
event.preventDefault();
//取消事件冒泡
event.stopPropagation();
//...还有好些不是很常用属性，这里不一一列举
}
</script>
</body>
</html>
三、jQuery $.event.fix方法定义原代码参考
fix: function(event)
{
if (event[expando] == true)
return event;
// store a copy of the original event object
// and "clone" to set read-only properties
var originalEvent = event;
event =
{
originalEvent: originalEvent
};
var props = "altKey attrChange attrName bubbles button cancelable charCode clientX clientY ctrlKey currentTarget data detail eventPhase fromElement handler keyCode metaKey newValue originalTarget pageX pageY prevValue relatedNode relatedTarget screenX screenY shiftKey srcElement target timeStamp toElement type view wheelDelta which".split(" ");
for (var i = props.length; i; i--)
event[props[i]] = originalEvent[props[i]];
// Mark it as fixed
event[expando] = true;
// add preventDefault and stopPropagation since
// they will not work on the clone
event.preventDefault = function()
{
// if preventDefault exists run it on the original event
if (originalEvent.preventDefault)
originalEvent.preventDefault();
// otherwise set the returnValue property of the original event to false (IE)
originalEvent.returnValue = false;
};
event.stopPropagation = function()
{
// if stopPropagation exists run it on the original event
if (originalEvent.stopPropagation)
originalEvent.stopPropagation();
// otherwise set the cancelBubble property of the original event to true (IE)
originalEvent.cancelBubble = true;
};
// Fix timeStamp
event.timeStamp = event.timeStamp || now();
// Fix target property, if necessary
if (!event.target)
event.target = event.srcElement || document; // Fixes #1925 where srcElement might not be defined either
// check if target is a textnode (safari)
if (event.target.nodeType == 3)
event.target = event.target.parentNode;
// Add relatedTarget, if necessary
if (!event.relatedTarget && event.fromElement)
event.relatedTarget = event.fromElement == event.target ? event.toElement : event.fromElement;
// Calculate pageX/Y if missing and clientX/Y available
if (event.pageX == null && event.clientX != null)
{
var doc = document.documentElement, body = document.body;
event.pageX = event.clientX + (doc && doc.scrollLeft || body && body.scrollLeft || 0) - (doc.clientLeft || 0);
event.pageY = event.clientY + (doc && doc.scrollTop || body && body.scrollTop || 0) - (doc.clientTop || 0);
}
// Add which for key events
if (!event.which && ((event.charCode || event.charCode === 0) ? event.charCode : event.keyCode))
event.which = event.charCode || event.keyCode;
// Add metaKey to non-Mac browsers (use ctrl for PC's and Meta for Macs)
if (!event.metaKey && event.ctrlKey)
event.metaKey = event.ctrlKey;
// Add which for click: 1 == left; 2 == middle; 3 == right
// Note: button is not normalized, so don't use it
if (!event.which && event.button)
event.which = (event.button & 1 ? 1 : (event.button & 2 ? 3 : (event.button & 4 ? 2 : 0)));
return event;
}
{
if (event[expando] == true)
return event;
// store a copy of the original event object
// and "clone" to set read-only properties
var originalEvent = event;
event =
{
originalEvent: originalEvent
};
var props = "altKey attrChange attrName bubbles button cancelable charCode clientX clientY ctrlKey currentTarget data detail eventPhase fromElement handler keyCode metaKey newValue originalTarget pageX pageY prevValue relatedNode relatedTarget screenX screenY shiftKey srcElement target timeStamp toElement type view wheelDelta which".split(" ");
for (var i = props.length; i; i--)
event[props[i]] = originalEvent[props[i]];
// Mark it as fixed
event[expando] = true;
// add preventDefault and stopPropagation since
// they will not work on the clone
event.preventDefault = function()
{
// if preventDefault exists run it on the original event
if (originalEvent.preventDefault)
originalEvent.preventDefault();
// otherwise set the returnValue property of the original event to false (IE)
originalEvent.returnValue = false;
};
event.stopPropagation = function()
{
// if stopPropagation exists run it on the original event
if (originalEvent.stopPropagation)
originalEvent.stopPropagation();
// otherwise set the cancelBubble property of the original event to true (IE)
originalEvent.cancelBubble = true;
};
// Fix timeStamp
event.timeStamp = event.timeStamp || now();
// Fix target property, if necessary
if (!event.target)
event.target = event.srcElement || document; // Fixes #1925 where srcElement might not be defined either
// check if target is a textnode (safari)
if (event.target.nodeType == 3)
event.target = event.target.parentNode;
// Add relatedTarget, if necessary
if (!event.relatedTarget && event.fromElement)
event.relatedTarget = event.fromElement == event.target ? event.toElement : event.fromElement;
// Calculate pageX/Y if missing and clientX/Y available
if (event.pageX == null && event.clientX != null)
{
var doc = document.documentElement, body = document.body;
event.pageX = event.clientX + (doc && doc.scrollLeft || body && body.scrollLeft || 0) - (doc.clientLeft || 0);
event.pageY = event.clientY + (doc && doc.scrollTop || body && body.scrollTop || 0) - (doc.clientTop || 0);
}
// Add which for key events
if (!event.which && ((event.charCode || event.charCode === 0) ? event.charCode : event.keyCode))
event.which = event.charCode || event.keyCode;
// Add metaKey to non-Mac browsers (use ctrl for PC's and Meta for Macs)
if (!event.metaKey && event.ctrlKey)
event.metaKey = event.ctrlKey;
// Add which for click: 1 == left; 2 == middle; 3 == right
// Note: button is not normalized, so don't use it
if (!event.which && event.button)
event.which = (event.button & 1 ? 1 : (event.button & 2 ? 3 : (event.button & 4 ? 2 : 0)));
return event;
}
作者：WebFlash
出处：http://webflash.cnblogs.com
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。
出处：http://webflash.cnblogs.com
本文版权归作者和博客园共有，欢迎转载，但未经作者同意必须保留此段声明，且在文章页面明显位置给出原文连接，否则保留追究法律责任的权利。
