function checkIP2(sIPAddress)
{
var exp=/^(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])\.(\d{1,2}|1\d\d|2[0-4]\d|25[0-5])$/;
var reg = sIPAddress.match(exp);
var ErrMsg="你输入的是一个非法的IP地址段！\nIP段为：:xxx.xxx.xxx.xxx（xxx为0-255)！"
var Msg="你输入的是一个合法的IP地址段！"
if(reg==null)
{
alert(ErrMsg);
}
else
{
alert(reg);
}
}