(Xojo Plugin) Send and Receive WebSocket Frame

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.

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

Dim ws As New Chilkat.WebSocket

// 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.

Dim rest As New Chilkat.Rest
// 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.
Dim success As Boolean
success = rest.Connect("websockets.chilkat.io",80,False,False)
success = ws.UseConnection(rest)
success = ws.AddClientHeaders()
Dim responseBodyIgnored As String
responseBodyIgnored = rest.FullRequestNoBody("GET","/wsChilkatEcho.ashx")
success = ws.ValidateServerHandshake()
If (success <> True) Then
    System.DebugLog(ws.LastErrorText)
    Return
End If

// 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.
Dim finalFrame As Boolean
finalFrame = True
success = ws.SendFrame("Hello World!",finalFrame)
If (success <> True) Then
    System.DebugLog(ws.LastErrorText)
    Return
End If

// Read an incoming frame.
success = ws.ReadFrame()
If (success <> True) Then
    System.DebugLog("Failed to receive a frame")
    System.DebugLog("ReadFrame fail reason = " + Str(ws.ReadFrameFailReason))
    System.DebugLog(ws.LastErrorText)
    Return
End If

// Show the string that was received.
Dim receivedStr As String
receivedStr = ws.GetFrameData()
System.DebugLog("Received: " + receivedStr)

// Close the websocket connection.
success = ws.SendClose(True,1000,"Closing this websocket.")
If (success <> True) Then
    System.DebugLog(ws.LastErrorText)
    Return
End If

// Read the Close response.
success = ws.ReadFrame()
If (success <> True) Then
    System.DebugLog("ReadFrame fail reason = " + Str(ws.ReadFrameFailReason))
    System.DebugLog(ws.LastErrorText)
    Return
End If

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

System.DebugLog("Success.")