public static Contact ToContactHeader(
	this SIPAddress address,
	AddrSpecType addSpecType,
	TransportType transportType,
	Nullable<int> expires = null
)

<ExtensionAttribute> 
Public Shared Function ToContactHeader ( 
	address As SIPAddress,
	addSpecType As AddrSpecType,
	transportType As TransportType,
	Optional expires As Nullable(Of Integer) = Nothing
) As Contact

public:
[ExtensionAttribute]
static Contact^ ToContactHeader(
	SIPAddress^ address, 
	AddrSpecType addSpecType, 
	TransportType transportType, 
	Nullable<int> expires = nullptr
)