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);

}

}