IP version for an address and/or port number in the URL.
property IPVersion: TIdIPversion;
IPVersion is a Public TIdIPversion property that represents the IP version used in the URL for the HTTP request.
The default value for IPVersion is Id_IPv4, but may be updated when an IP address (and optional port number) is found in the URL during preparation of the request for the HTTP client.
URL TIdIPversion Id_IPv4