兼容IE和FireFox浏览器的get event事件写法

<script>
function getEvent()  
{  
if(!(document.getElementById&& (navigator.appName=="Netscape")))  return window.event;    
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; 
}
//测试函数，打印所有event支持的属性，包括 clientX、target、srcElement等
function test(){
	var evt = getEvent();
	//(evt.srcElement || evt.target);
	var html = '<ul>';
	var text = '';
	for(var i in evt){
		try{
			if(typeof(evt[i]) == 'object' && (i=='srcElement'||i=='target')){
				html +='<li style="color:green">'+ i+':<ul>';
				text +=''+i+':';
				for(var ii in evt[i]){
					try{
						html +='<li>'+ ii+':'+evt[i][ii].toString()+'</li>';
						text +='	'+ii+':'+evt[i][ii].toString()+"\r\n";;
					}catch(E){
						html +='<li>'+ii+':'+E.toString()+'</li>';
						text +='	'+ii+':'+E.toString()+"\r\n";
					}
				}
				html +='</ul></li>';
			}else

			html +='<li>'+ i+':'+evt[i]+'</li>';
			text +=''+i+':'+evt[i]+"\r\n";;
		}catch(E){
			html +='<li>'+i+':'+E.toString()+'</li>';
			text +=''+i+':'+E.toString()+"\r\n";
		}
	}
	html += '</ul>';
	document.getElementById('D1').innerHTML = html;
	if(document.getElementById('D2').innerText)
	document.getElementById('D2').innerText = text;
	else document.getElementById('D2').innerHTML = text;

}

/**/
</script>

<div>
<table width="100%">
<tr>
  <td>testCode
</td><td><input id="testID" value="Click Me!" type="button" onClick="test()">
</td>
</tr>
<tr>

  <td width="50%" valign="top"><textarea style="width:100%" rows="30" id="D2">TEST</textarea></td>
  <td width="50%"><div  id="D1" style="overflow:auto; height:450px"></div></td>
  </tr>
</table>
</div>