IsValidIPAddress

public static bool IsValidIPAddress(this string s)
{
    return Regex.IsMatch(s, 
            @"\b(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b");
}
Example:
//returns false
string s = "192.168.1.256";
bool b = s.IsValidIPAddress();
//returns true
string s = "192.168.1.254";
bool b = s.IsValidIPAddress();

Description

Validates whether a string is a valid IPv4 address.

Details

Double click on the code to select all.

 

;