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); }}