TsgcQUICClient › Properties › IPVersion
Address family of the inherited Indy UDP socket. The QUIC connection picks its own family from Host, so this property does not change it.
TIdIPVersion, one of Id_IPv4 or Id_IPv6.
property IPVersion: TIdIPVersion read GetIPVersion write SetIPVersion;Id_IPv4
IPVersion is inherited from the UDP client base class. It reads and writes straight through to the Indy UDP socket, where it selects the address family the socket is opened with.
The built-in QUIC engine does not use that socket. It creates its own and chooses the address family from Host, taking a value that contains a colon as an IPv6 literal and resolving a host name over both families. Setting IPVersion therefore has no effect on the QUIC connection, and you do not need to set it to reach an IPv6 server. Put the address or the name in Host and leave this property alone.
The property is public rather than published, so it can only be set in code. It is kept for consistency with the rest of the UDP client family.
This member is currently available in the Delphi/C++Builder implementation only. The .NET implementation resolves the address family from the host through System.Net.Quic.
oClient := TsgcQUICClient.Create(nil);
// an IPv6 literal in Host is enough, IPVersion is not consulted
oClient.Host := '::1';
oClient.Port := 443;
oClient.Connect;