Lianja

Send and Receive WebSocket Frame

See more WebSocket Examples

Demonstrates how to send a websocket text frame to a websocket echo server. This example uses Chilkat's websocket test echo server at ws://websockets.chilkat.io/wsChilkatEcho.ashx

Note: The websockets.chilkat.io server imposes the following limitations:
Messages must be 16K or less, and each connection is limited to a max of 16 echoed messages.

Lianja

llSuccess = .F.

// This example requires the Chilkat API to have been previously unlocked.
// See Global Unlock Sample for sample code.

loWs = createobject("CkWebSocket")

// For brevity, this example does not check for errors when etablishing the WebSocket connection.
// See Establish WebSocket Connection for more complete sample code for making the connection.

loRest = createobject("CkRest")
// Connect to websockets.chilkat.io
// IMPORTANT: websockets.chilkat.io accepts frames of up to 16K in size and echoes them back.
// IMPORTANT: The websockets.chilkat.io server imposes the following limitations: 
// ---------- Messages must be 16K or less, and each connection is limited to a max of 16 echoed messages.
llSuccess = loRest.Connect("websockets.chilkat.io",80,.F.,.F.)
loWs.UseConnection(loRest)
loWs.AddClientHeaders()
lcResponseBodyIgnored = loRest.FullRequestNoBody("GET","/wsChilkatEcho.ashx")
llSuccess = loWs.ValidateServerHandshake()
if (llSuccess <> .T.) then
    ? loWs.LastErrorText
    release loWs
    release loRest
    return
endif

// This example demonstrates sending a frame and receiving a text frame.

// Send a frame containing the string "Hello World!"
// This will be the first and final frame, and therefore this constitutes the entire message.
llFinalFrame = .T.
llSuccess = loWs.SendFrame("Hello World!",llFinalFrame)
if (llSuccess <> .T.) then
    ? loWs.LastErrorText
    release loWs
    release loRest
    return
endif

// Read an incoming frame.
llSuccess = loWs.ReadFrame()
if (llSuccess <> .T.) then
    ? "Failed to receive a frame"
    ? "ReadFrame fail reason = " + str(loWs.ReadFrameFailReason)
    ? loWs.LastErrorText
    release loWs
    release loRest
    return
endif

// Show the string that was received.
lcReceivedStr = loWs.GetFrameData()
? "Received: " + lcReceivedStr

// Close the websocket connection.
llSuccess = loWs.SendClose(.T.,1000,"Closing this websocket.")
if (llSuccess <> .T.) then
    ? loWs.LastErrorText
    release loWs
    release loRest
    return
endif

// Read the Close response.
llSuccess = loWs.ReadFrame()
if (llSuccess <> .T.) then
    ? "ReadFrame fail reason = " + str(loWs.ReadFrameFailReason)
    ? loWs.LastErrorText
    release loWs
    release loRest
    return
endif

// Should receive the "Close" opcode.
? "Received opcode: " + loWs.FrameOpcode
// Should be the same status code we sent (1000)
? "Received close status code: " + str(loWs.CloseStatusCode)
// The server may echo the close reason.  If not, this will be empty.
? "Echoed close reason: " + loWs.CloseReason

? "Success."


release loWs
release loRest