TWSocketServer

Main page -> ICS component reference -> TWSocketServer and TSslWSocketServer

Overview

unit		OverbyteIcsWSocketS.pas
inheritance		TWSocket

TWSocketServer will normally be used to listen on a given TCP port. When a client connects, it will instantiate a new TWSocketClient component to handle communication with client. Normally you will derive your own component from TWSocketClient to add private data and methods to handle your processing needs. You tell TWSocketServer which component class it has to instantiate using ClientClass property. You have to initialize each instance created to handle each client from OnClientConnect event handler. TWSocketServer maintain a list of connected clients. You can access it using Client[] indexed property. ClientCount property is the size of Client[] array.

Since it is derived from TWSocket and TSslWSocket, lots of properties and events are unused and not listed here. Properties and events that have a meaning in both server or client component are listed here.

Note that TWSocketServer is only usable for incoming TCP connections. Use TWSocket if you need to use UDP.

Note: When a TWSocketClient is closed, it automatically frees itself. With a normal TWSocket, the programmer is responsible for freeing the object.

Properties

Addr		Server listen IP address, IPv4 or IPv6, maybe 0.0.0.0 or :: to listen on all available addresses, ignored if any IcsHosts specified. IP address must exist and not be in use elsewhere for the same port.
Banner		A short message line sent when each client connects. Should generally be blank.
BannerTooBusy		A short message sent when a client connects and the number of clients already exceeds the MaxClients limit.
Client		Indexed property giving access to all connected clients.
ClientClass		Class the component use to handle each incoming connection.
ClientCount		Number of connected clients.
Handle		Handle of the hidden window used for socket operation.
HSocket		Underlying winsock socket handle.
IcsHosts		Allows one or more TIcsHosts to be set, as TIcsHostCollection, an alternate way for specifying multiple listeners that allows multiple hosts to be specified, each with one or two IP addresses and non-SSL and SSL port bindings, SSL certificates and private key (perhaps combined in a bundle), SSL context and security level, and other web server host related properties (used by higher level components). Each IcsHost has one or more HostNames to which it will recognise, that can share IP addresses.
LastError		Last error which occurred.
ListenBacklog		How many pending connection the system has to accept before denying access.
MaxClients		Max number of connected client. All subsequent connections will be closed.
MultiListenSockets		Allows one or more extra server listen IP addresses and ports to be specified, as type TWSocketMultiListenCollection, allowing server to listen on several IP addresses/ports at the same time, in addition to the that specified as Addr/Port props. Each TWSocketMultiListenItem has Addr, Port, SocketFamily, SslEnable and ListenBacklog properties. Better to use IcsHosts for new applications which does the same, ignored if any IcsHosts specified.
MultiListenIndex		Read only, which listen socket accepted last connection, -1 if default Addr.Poprt used, 0 or above is index into MultiListenSockets collection.
Port		TCP port or service name to listen to, usually 80 or 443, ignored if any IcsHosts specified.
PortNum		Readonly property with numeric value corresponding to Port.
Proto		Protocol used. Must be 'tcp'.
SocketFamily		IP address socket family as TSocketFamily, from sfIPv4, sfIPv6.
SslEnable		True if an SSL connection should be negotiated. ignored if any IcsHosts specified.
SslContext		Assign to an TSslContext component for SSL support, where SSL certificates, keys, protocols and ciphers are specified, ignored if any IcsHosts specified.
State		Gives the state of the component.

Methods

Abort		Abort current asynchronous operation.
Close		Stops listening, does not disconnect connected clients.
CloseDelayed		Same as Close however it's executed delayed, after current event has finished.
Create		Create a new instance of the component.
Destroy		Destroy the current instance.
IsClient		Check if a component reference is one of the connected clients.
Listen		Start accepting connections.
MessageLoop		Internal message loop.
MessagePump		Internal message pump.
ProcessMessage		Process a single message.
ProcessMessages		Process messages until message queue is empty.
Release		Destroy the current instance after the current event is terminated.
ThreadAttach		Detach from current thread.
ThreadDetach		Attach to current thread.

Events

OnBgException		When a background exception occurs.
OnChangeState		When the component state changes.
OnClientConnect		When a new client is connecting.
OnClientCreate		When a new client component instance is created.
OnClientDisconnect		When a client disconnects.
OnError		When an error occurs. Better to use exception handling.
OnMessagePump		To call your own external message pump instead of built-in one.

How to

• Stop accepting connections

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ICS Components Reference