[问题分析] 问个关于css的问题

//鼠标经过
document.onmouseover=ButtonOnMouseOver
document.onmouseout=ButtonOnMouseOut
function ButtonOnMouseOver(){
try{
if ((event.srcElement.type=="button")||(event.srcElement.type=="submit")||(event.srcElement.type=="reset"))
{
switch(event.srcElement.className)
{
case "button01-out" :
event.srcElement.className="button01-over"
break
case "button02-out" :
event.srcElement.className="button02-over"
break
}
}
}catch(exception){}
}
//鼠标离开
function ButtonOnMouseOut()
{
try{
if ((event.srcElement.type=="button")||(event.srcElement.type=="submit")||(event.srcElement.type=="reset"))
{
switch(event.srcElement.className)
{
case "button01-over" :
event.srcElement.className="button01-out"
break
case "button02-over" :
event.srcElement.className="button02-out"
break
}
}
}catch(exception){}