If you have users enter URLs and you would like to check them to make sure they exist before you save them to the database, here is the code:
public static bool UrlIsValid(string smtpHost)
{
bool br = false;
try {
IPHostEntry ipHost = Dns.Resolve(smtpHost);
br = true;
}
catch (SocketException se) {
br = false;
}
return br;
}
To use, simply call UrlIsValid with the host name, for example:
string url = "www.google.com";
if(UrlIsValid(url)) {
Response.Write("The URL '" + url + "' is valid.");
} else {
Response.Write("The URL '" + url + "' is NOT valid.");
}