JavaScript多域名转向

<script>
try {
if( self.location == "http://域名一/index.html" )
{
top.location.href = "http://域名一/目录";
}
else if( self.location == "http://域名二/index.html" )
{
top.location.href = "http://域名二/目录";
}
else
{
document.write("错误的网址")
}
catch(e){}
</script>