public bool IsCorrenctIP(string ip)
{ 
string pattrn=@"(/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])";
if(System.Text.RegularExpressions.Regex.IsMatch(ip,pattrn)) 
{ 
return true; 
}
else
{
return false;

}
}

public bool IsValidIP(string ip) 
{ 
if (System.Text.RegularExpressions.Regex.IsMatch(ip,"[0-9]{1,3}//.[0-9]{1,3}//.[0-9]{1,3}//.[0-9]{1,3}")) 
{ 
string[] ips = ip.Split('.'); 
if (ips.Length == 4 || ips.Length == 6) 
{ 
if(System.Int32.Parse(ips[0]) < 256 && System.Int32.Parse(ips[1]) < 256 & System.Int32.Parse(ips[2]) < 256 & System.Int32.Parse(ips[3]) < 256) 
return true; 
else 
return false; 
} 
else 
return false;

} 
else 
return false; 
}