jQuery的浏览器兼容性策略（转载）

之前写过一篇日志（http://shawphy.com/article.asp?id=34），说FF没有cancelBubble，所以要做兼容，其实多虑了，JQ已经为我们做好兼容性了。

也就是说，要阻止冒泡，直接使用
$("a").click(function(e) {
e.stopPropagation();
})
这样即可。
她还修正了preventDefault ,target ,relatedTarget,pageX/Y,event.which(确定按了键盘或者鼠标上的哪个按键。)

多的不说，大家自己看代码吧(jQuery 1.2.3 /line:2093-2149)

[quote] fix: function(event) {
// store a copy of the original event object
// and clone to set read-only properties
var originalEvent = event;
event = jQuery.extend({}, originalEvent);

// 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 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 = originalEvent.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;
},
[/quote]