The port number defines the protocol port used for contacting the server referenced in the URI. If a port is not specified as part of the URI, the Port property returns the default value for the protocol. If there is no default port number, this property returns -1.
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.