JavaScript事件委托实例分析

var addEvent = function (elem, eventType, func) {
if ( elem.addEventListener )
addEvent = function (elem, eventType, func) {
elem.addEventListener(eventType, func, false);
};
else if ( elem.attachEvent )
addEvent = function (elem, eventType, func) {
elem.attachEvent('on' + eventType, func);
};
addEvent(elem, eventType, func);
};
var delegateEvent = function (elem, childElems, eventType, func, args) {
addEvent(elem, eventType, function (e) {
var evt = e || window.event;
var elem = evt.target || evt.srcElement;
if ( elem.nodeName.toLowerCase() == childElems.toLowerCase() ) {
func(elem, args);
}
});
};