var testButton=document.getElementById("testButton");
function handlerTest()
{
var oEvent=window.event;//for IE
//var oEvent=arguments[0];// for DOM
if(oEvent.type=="click")
{
alert("click");
}
else if(oEvent.type=="mouseover")
{
alert("mouseover");
}
else
{
alert(oEvent.keycode);
}
}
testButton.onclick=handlerTest;
testButton.onmouseover=handlerTest;
html元素如下：<input id="testButton" type="button" value="testButton" />