Js获取事件对象代码

<input type="button" id="test" value="点我测试" />
<script type="text/javascript">
var testBtn = document.getElementById('test');
testBtn.onclick = testFun;
function testFun(e)
{
var evt = e || window.event;
alert(evt);
}
</script>

<input type="button" id="test" value="点我测试" />
<script type="text/javascript">
var testBtn = document.getElementById('test');
if(window.addEventListener)
{
testBtn.addEventListener('click', testFun, false);
}
else if(window.attachEvent)
{
testBtn.attachEvent('onclick', testFun);
}
function testFun(e)
{
var evt = e || window.event;
alert(evt);
}
</script>

<input type="button" id="test_1" value="点我测试" onclick="testFun_1()" />
<script type="text/javascript">
function testFun_1()
{
//此处如何获得？
}
</script>

<input type="button" id="test_1" value="点我测试" onclick="testFun_1()" />
<script type="text/javascript">
function testFun_1()
{
var evt = getEvent();
alert(evt);
}
function getEvent(){
if(window.event) return window.event; //这里用对象检测更为妥当
func=getEvent.caller;
while(func!=null){
var arg0=func.arguments[0];
if(arg0){
if((arg0.constructor==Event || arg0.constructor ==MouseEvent)
|| (typeof(arg0)=="object" && arg0.preventDefault && arg0.stopPropagation)){
return arg0;
}
}
func=func.caller;
}
return null;
}
</script>