C# Regex Match gives wrong result

Question

 var hostName = "tenant1.example.be";

 var match = Regex.Match(hostName, @"([A-Za-z0-9]+)\.example\.be$", RegexOptions.IgnoreCase);
 var subdomain = match.Success ? match.Value : null;

Result for subdomain is always: tenant1.example.be instead of just tenant1 .

Anyone?

Answer 1

您只需要匹配的第一组：

var subdomain = match.Success ? match.Groups[1].Value : null;