Internet Controls

The Internet tab provides 9 controls for web browsing, HTTP/FTP networking, email, WebSocket communication, and TCP/UDP socket programming. All controls are cross-platform and use non-blocking I/O internally.

TWebView CT_WEBVIEW = 62

Embeds a full web browser inside a form. Renders HTML content or navigates to URLs using the platform's native web engine.

Property	Type	Default	Description
cURL	String	""	URL to navigate to
cHTML	String	""	Raw HTML content to render
lCanGoBack	Logical	.F.	Whether navigation history allows going back (read-only)
lCanGoForward	Logical	.F.	Whether navigation history allows going forward (read-only)
cTitle	String	""	Page title (read-only)

Event	Category	Description
OnNavigate	Navigation	Fired before navigating to a new URL. Return .F. to cancel
OnLoad	Navigation	Page finished loading
OnError	Error	Navigation or rendering error occurred

Platform	Native Widget
Windows	WebView2 (Chromium-based Edge)
macOS	WKWebView (WebKit)
Linux	WebKitGTK (WebKit2)

TWebServer CT_WEBSERVER = 71

Embedded HTTP/HTTPS server. Allows your application to serve web pages, REST APIs, or act as a local service endpoint.

Property	Type	Default	Description
nPort	Numeric	8080	Listening port number
cHost	String	"0.0.0.0"	Bind address
cDocumentRoot	String	""	Root directory for static files
lSSL	Logical	.F.	Enable HTTPS
cCertFile	String	""	Path to SSL certificate file
cKeyFile	String	""	Path to SSL private key file
nMaxConnections	Numeric	256	Maximum simultaneous connections

Event	Category	Description
OnRequest	Action	HTTP request received. Params: oRequest, oResponse
OnConnect	Connection	New client connected
OnDisconnect	Connection	Client disconnected
OnStart	Lifecycle	Server started listening
OnStop	Lifecycle	Server stopped
OnError	Error	Server error occurred

TWebSocket CT_WEBSOCKET = 72

WebSocket client for real-time bidirectional communication with a server.

Property	Type	Default	Description
cURL	String	""	WebSocket server URL (ws:// or wss://)
cProtocol	String	""	Sub-protocol to negotiate
lAutoReconnect	Logical	.F.	Automatically reconnect on disconnection
nReconnectDelay	Numeric	3000	Delay in ms before reconnect attempt

Event	Category	Description
OnOpen	Connection	Connection established
OnMessage	Data	Message received from server
OnClose	Connection	Connection closed
OnError	Error	Connection or protocol error

THttpClient CT_HTTPCLIENT = 73

HTTP client for making REST API calls, downloading files, and general HTTP communication.

Property	Type	Default	Description
cURL	String	""	Request URL
cMethod	String	"GET"	HTTP method (GET, POST, PUT, DELETE, PATCH)
aHeaders	Array	{}	Request headers as key-value pairs
cBody	String	""	Request body content
nTimeout	Numeric	30000	Request timeout in milliseconds
nStatusCode	Numeric	0	Response status code (read-only)

Event	Category	Description
OnResponse	Data	Response received. Params: nStatus, cBody, aHeaders
OnProgress	Data	Download/upload progress. Params: nCurrent, nTotal
OnError	Error	Request failed

TFtpClient CT_FTPCLIENT = 74

FTP/FTPS client for file transfer operations.

Property	Type	Default	Description
cHost	String	""	FTP server hostname
nPort	Numeric	21	Server port
cUser	String	""	Login username
cPassword	String	""	Login password
lPassiveMode	Logical	.T.	Use passive mode for data transfers
lSSL	Logical	.F.	Use FTPS (FTP over TLS)

Event	Category	Description
OnConnect	Connection	Successfully connected to server
OnTransfer	Data	File transfer progress. Params: cFile, nBytes, nTotal
OnError	Error	Connection or transfer error

TSmtpClient CT_SMTPCLIENT = 75

SMTP client for sending email messages with attachments.

Property	Type	Default	Description
cHost	String	""	SMTP server hostname
nPort	Numeric	587	Server port (25, 465, or 587)
lSSL	Logical	.T.	Use TLS/SSL encryption
cUser	String	""	Authentication username
cPassword	String	""	Authentication password
cFrom	String	""	Sender email address
cTo	String	""	Recipient email address(es), comma-separated
cSubject	String	""	Email subject line
cBody	String	""	Email body content

Event	Category	Description
OnSend	Action	Email sent successfully
OnError	Error	Send or connection error

TTcpServer CT_TCPSERVER = 76

TCP socket server. Listens for incoming connections and manages multiple clients.

Property	Type	Default	Description
nPort	Numeric	0	Listening port
cHost	String	"0.0.0.0"	Bind address
nMaxConnections	Numeric	128	Maximum simultaneous connections
lActive	Logical	.F.	Server is currently listening (read-only)

Event	Category	Description
OnAccept	Connection	New client connection accepted. Params: oClient
OnReceive	Data	Data received from client. Params: oClient, cData
OnDisconnect	Connection	Client disconnected. Params: oClient

TTcpClient CT_TCPCLIENT = 77

TCP socket client. Connects to a remote server for stream-based communication.

Property	Type	Default	Description
cHost	String	""	Remote server hostname or IP
nPort	Numeric	0	Remote server port
nTimeout	Numeric	10000	Connection timeout in milliseconds
lConnected	Logical	.F.	Connection status (read-only)

Event	Category	Description
OnConnect	Connection	Successfully connected to server
OnReceive	Data	Data received from server. Params: cData
OnDisconnect	Connection	Disconnected from server

TUdpSocket CT_UDPSOCKET = 78

UDP datagram socket for connectionless, low-latency communication.

Property	Type	Default	Description
nPort	Numeric	0	Local port to bind to
lBroadcast	Logical	.F.	Enable broadcast mode
cHost	String	"0.0.0.0"	Bind address

Event	Category	Description
OnReceive	Data	Datagram received. Params: cData, cSenderIP, nSenderPort

Code Example: Simple Web Server

// A simple web server that responds to HTTP requests

FUNCTION Main()

   LOCAL oServer

   oServer := TWebServer():New()
   oServer:nPort := 8080
   oServer:cDocumentRoot := "./public"

   oServer:OnRequest := { |oReq, oRes| HandleRequest( oReq, oRes ) }
   oServer:OnStart   := { || QOut( "Server running on port 8080" ) }
   oServer:OnError   := { |e| QOut( "Error: " + e:Description ) }

   oServer:Start()

   // Keep the application running
   WAIT "Press any key to stop..."

   oServer:Stop()

RETURN NIL

FUNCTION HandleRequest( oReq, oRes )

   DO CASE
      CASE oReq:cPath == "/api/hello"
         oRes:cContentType := "application/json"
         oRes:cBody := '{"message": "Hello from HarbourBuilder!"}'

      CASE oReq:cPath == "/api/time"
         oRes:cContentType := "application/json"
         oRes:cBody := '{"time": "' + Time() + '"}'

      OTHERWISE
         oRes:nStatus := 404
         oRes:cBody := "Not Found"
   ENDCASE

RETURN NIL