Methods

Methods

The Winsock control has only a handful of methods. With a couple of exceptions, most of the method names mirror their Winsock equivalents. The method to read pending data is named GetData. Usually, you would call the GetData method once the DataArrival event is triggered, notifying you that data has arrived. The method for sending data is named SendData. In addition, a method named PeekData is similar to calling the Winsock recv function with the MSG_PEEK option. As always, message peeking is evil and should be avoided at all costs. Table 14-3 lists the available methods with their parameters. The methods will be discussed in more detail in the client and server example sections later in this chapter.

Table 14-3 Winsock Control Methods

Method	Parameters	Return Value	Description
Accept	RequestID	Void	For TCP connections only. Use this method to accept incoming connections when handling a ConnectionRequest event.
Bind	LocalPort LocalIP	Void	Binds the socket to the given local port and IP. Use Bind if you have multiple network adapters. Bind must be called before Listen.
Close	None	Void	Closes the connection or the listening socket.
Connect	RemoteHost RemotePort	Void	Establishes a TCP connection to the given RemoteHost on the given RemotePort number.
GetData	Data Type MaxLen	Void	Retrieves the current data pending. The Type and MaxLen parameters are optional. The Type parameter defines the type of data to be read. The MaxLen parameter specifies how many bytes or characters to retrieve. GetData ignores the MaxLen parameter for types other than byte array and string.
Listen	None	Void	Creates a socket and places it in listen mode. Listen is used for TCP connections only.
PeekData	Data Type MaxLen	Void	Behaves exactly like GetData except that the data is not removed from the system's buffer.
SendData	Data	Void	Sends data to the remote computer. If a UNICODE string is passed, it will be converted to an ANSI string first. Always use a byte array for binary data.