cWebSocketClient Class Reference

📋 Class Overview

cWebSocketClient is a WebSocket client implementation class that provides functionality to connect to WebSocket servers, send/receive messages, and handle automatic handshakes.

📡 Event List

Event Name	Trigger Timing	Parameters
`OnOpen`	Connection successfully established	None
`OnClose`	Connection closed	`Code` (Close code), `Reason` (Close reason)
`OnTextMessage`	Text message received	`Message` (Message content)
`OnBinaryMessage`	Binary message received	`Data()` (Byte array)
`OnError`	Error occurred	`Description` (Error description)
`OnPong`	Pong response received	`Data()` (Pong payload)

🔧 Property Reference

State - Connection State

Type: WsState (Enum)
Read/Write: Read-only

Values:

Constant	Value	Description
`WS_STATE_CLOSED`	0	Closed
`WS_STATE_CONNECTING`	1	Connecting/handshaking
`WS_STATE_OPEN`	2	Connected, can send messages
`WS_STATE_CLOSING`	3	Closing

Example:

If m_Client.State = WS_STATE_OPEN Then
    m_Client.SendText "Hello"
Else
    Debug.Print "Not connected"
End If

URL - Connection URL

Type: String
Read/Write: Read-only

Description: The current or last connected WebSocket URL.

Example:

Debug.Print "Connected to: " & m_Client.URL
' Output: Connected to: ws://127.0.0.1:8080

Host - Server Hostname

Type: String
Read/Write: Read-only

Description: Server hostname or IP address parsed from URL.

Example:

Debug.Print "Server: " & m_Client.Host

Port - Server Port

Type: Long
Read/Write: Read-only

Description: Server port number parsed from URL.

Example:

Debug.Print "Port: " & m_Client.Port

AutoPing - Auto Ping

Type: Boolean
Read/Write: Read/Write

Description: Whether to enable automatic Ping (keepalive feature). Default is False.

Example:

' Enable auto Ping
m_Client.AutoPing = True

' Disable auto Ping
m_Client.AutoPing = False

PingInterval - Ping Interval

Type: Long
Read/Write: Read/Write

Description: Auto Ping interval time in milliseconds. Default is 30000 (30 seconds).

Example:

' Set Ping interval to 20 seconds
m_Client.PingInterval = 20000

🚀 Method Reference

Connect - Connect to Server

Syntax:

Public Sub Connect(ByVal WebSocketURL As String, Optional ByVal SubProtocol As String = "")

Parameters:

Parameter	Type	Description
`WebSocketURL`	String	WebSocket server URL, format: `ws[s]://host[:port][/path][?query]`
`SubProtocol`	String (Optional)	WebSocket sub-protocol

URL Format:

Standard format: ws://example.com:8080/chat
Default port: ws://example.com/chat (default 80)
Query parameters: ws://example.com/chat?token=abc123
Secure connection: wss://example.com (not yet implemented)

Example:

' Basic connection
m_Client.Connect "ws://127.0.0.1:8080"

' Connection with path
m_Client.Connect "ws://example.com/chat"

' Connection with query parameters
m_Client.Connect "ws://example.com/chat?token=abc123"

' Specify sub-protocol
m_Client.Connect "ws://example.com/chat", "chat.v1"

Error Handling:

Private Sub cmdConnect_Click()
    On Error GoTo EH

    m_Client.Connect "ws://example.com:8080"
    Exit Sub

EH:
    Debug.Print "Connection failed: " & Err.Description
End Sub

CloseConnection - Close Connection

Syntax:

Public Sub CloseConnection(Optional ByVal Code As WsCloseCode = WS_CLOSE_NORMAL, _
                          Optional ByVal Reason As String = "")

Parameters:

Parameter	Type	Description
`Code`	WsCloseCode (Optional)	Close status code, default `WS_CLOSE_NORMAL`
`Reason`	String (Optional)	Close reason

Common Close Codes:

m_Client.CloseConnection WS_CLOSE_NORMAL, "Normal closure"
m_Client.CloseConnection WS_CLOSE_GOING_AWAY, "User leaving"
m_Client.CloseConnection WS_CLOSE_PROTOCOL_ERROR, "Protocol error"

Example:

' Normal close
m_Client.CloseConnection

' Specify close code and reason
m_Client.CloseConnection WS_CLOSE_GOING_AWAY, "User logout"

' Auto disconnect on form close
Private Sub Form_Unload(Cancel As Integer)
    m_Client.CloseConnection WS_CLOSE_GOING_AWAY, "Application closing"
End Sub

SendText - Send Text Message

Syntax:

Public Sub SendText(ByVal Message As String)

Parameters:

Parameter	Type	Description
`Message`	String	Text message to send

Description: Message is automatically converted to UTF-8 encoding and WebSocket frame header is added. Frames sent by client are automatically masked.

Example:

' Send simple text
m_Client.SendText "Hello WebSocket!"

' Send JSON data
Dim sJSON As String
sJSON = "{""type"":""message"", ""content"":""Hello""}"
m_Client.SendText sJSON

' Send multi-line text
m_Client.SendText "First line" & vbCrLf & "Second line"

Error Handling:

On Error GoTo EH
m_Client.SendText "Hello"
Exit Sub
EH:
Debug.Print "Send failed: " & Err.Description

SendBinary - Send Binary Message

Syntax:

Public Sub SendBinary(Data() As Byte)

Parameters:

Parameter	Type	Description
`Data()`	Byte()	Binary data to send

Example:

' Send byte array
Dim baData() As Byte
baData = StringToBytes("Hello")
m_Client.SendBinary baData

' Send image data
Dim baImage() As Byte
baImage = LoadImageToByteArray()
m_Client.SendBinary baImage

' Send serialized object
Dim baObj() As Byte
baObj = SerializeObject(myObject)
m_Client.SendBinary baObj

SendPing - Send Ping Frame

Syntax:

Public Sub SendPing(Optional Payload As Variant)

Parameters:

Parameter	Type	Description
`Payload`	Variant (Optional)	Ping payload, can be string or byte array

Description: Used for connection keepalive, server automatically replies with Pong frame.

Example:

' Send empty Ping (keepalive)
m_Client.SendPing

' Send Ping with data
m_Client.SendPing "ping"

' Send Ping with binary data
Dim baData() As Byte
baData = StringToUTF8("ping")
m_Client.SendPing baData

' Measure latency
Dim lStartTime As Long
lStartTime = GetTickCount()
m_Client.SendPing "ping"

Private Sub m_Client_OnPong(Data() As Byte)
    Dim lElapsed As Long
    lElapsed = GetTickCount() - lStartTime
    Debug.Print "Latency: " & lElapsed & " ms"
End Sub

📡 Event Details

OnOpen - Connection Opened

Syntax:

Event OnOpen()

Description: Triggered after WebSocket handshake successful, now you can start sending messages.

Example:

Private Sub m_Client_OnOpen()
    Debug.Print "Successfully connected to WebSocket server"

    ' Send welcome message
    m_Client.SendText "Hello Server!"

    ' Update UI
    lblStatus.Caption = "Connected"
    cmdSend.Enabled = True
End Sub

OnClose - Connection Closed

Syntax:

Event OnClose(ByVal Code As WsCloseCode, ByVal Reason As String)

Parameters:

Parameter	Type	Description
`Code`	WsCloseCode	Close status code
`Reason`	String	Close reason

Example:

Private Sub m_Client_OnClose(ByVal Code As WsCloseCode, ByVal Reason As String)
    Debug.Print "Connection closed"
    Debug.Print "Status code: " & Code
    Debug.Print "Reason: " & Reason

    ' Handle based on close code
    Select Case Code
        Case WS_CLOSE_NORMAL
            Debug.Print "Normal closure"
        Case WS_CLOSE_ABNORMAL
            Debug.Print "Abnormal closure"
            ' Try to reconnect
            If m_bAutoReconnect Then
                tmrReconnect.Enabled = True
            End If
        Case WS_CLOSE_GOING_AWAY
            Debug.Print "Server closed"
        Case Else
            Debug.Print "Other reason: " & Reason
    End Select

    ' Update UI
    lblStatus.Caption = "Disconnected"
    cmdSend.Enabled = False
End Sub

OnTextMessage - Text Message Received

Syntax:

Event OnTextMessage(ByVal Message As String)

Parameters:

Parameter	Type	Description
`Message`	String	Received text message (UTF-8 decoded)

Example:

Private Sub m_Client_OnTextMessage(ByVal Message As String)
    Debug.Print "Received message: " & Message

    ' Handle JSON message
    If Left$(Message, 1) = "{" Then
        Dim sType As String
        sType = GetJSONField(Message, "type")
        
        Select Case sType
            Case "chat"
                DisplayChatMessage Message
            Case "notification"
                DisplayNotification Message
        End Select
    Else
        ' Simple text message
        txtMessages.Text = txtMessages.Text & Message & vbCrLf
    End If
End Sub

OnBinaryMessage - Binary Message Received

Syntax:

Event OnBinaryMessage(Data() As Byte)

Parameters:

Parameter	Type	Description
`Data()`	Byte()	Received binary data

Example:

Private Sub m_Client_OnBinaryMessage(Data() As Byte)
    Debug.Print "Received binary message: " & (UBound(Data) + 1) & " bytes"

    ' Check data type (assume first 4 bytes are type identifier)
    If UBound(Data) >= 3 Then
        Dim lType As Long
        lType = CLng(Data(0)) * 256& ^ 3 + CLng(Data(1)) * 256& ^ 2 + _
                CLng(Data(2)) * 256& + CLng(Data(3))

        Select Case lType
            Case 1 ' Text
                Dim sText As String
                sText = UTF8ToString(ExtractData(Data, 4))
                Debug.Print "Text data: " & sText

            Case 2 ' Image
                DisplayImage ExtractData(Data, 4)

            Case 3 ' Custom
                ProcessCustomData ExtractData(Data, 4)
        End Select
    End If
End Sub

OnError - Error Occurred

Syntax:

Event OnError(ByVal Description As String)

Parameters:

Parameter	Type	Description
`Description`	String	Error description

Example:

Private Sub m_Client_OnError(ByVal Description As String)
    Debug.Print "Error: " & Description

    ' Show error alert
    MsgBox "Error occurred: " & Description, vbExclamation

    ' Log error
    LogError Description

    ' Update UI
    lblStatus.Caption = "Error"
End Sub

OnPong - Pong Received

Syntax:

Event OnPong(Data() As Byte)

Parameters:

Parameter	Type	Description
`Data()`	Byte()	Pong payload (corresponds to Ping data)

Description: Usually used for measuring network latency or confirming connection activity.

Example:

Private m_lPingTimes() As Long
Private m_lPingIndex As Long

Private Sub SendPingForLatency()
    ReDim m_lPingTimes(1) As Long
    m_lPingIndex = 0
    m_lPingTimes(0) = GetTickCount()
    m_Client.SendPing "ping"
End Sub

Private Sub m_Client_OnPong(Data() As Byte)
    m_lPingTimes(1) = GetTickCount()
    Dim lLatency As Long
    lLatency = m_lPingTimes(1) - m_lPingTimes(0)
    Debug.Print "Network latency: " & lLatency & " ms"

    ' Update UI
    lblLatency.Caption = lLatency & " ms"
End Sub

📝 Complete Example

Basic Client Example

Private WithEvents m_Client As cWebSocketClient

Private Sub Form_Load()
    Set m_Client = New cWebSocketClient
End Sub

Private Sub cmdConnect_Click()
    m_Client.Connect "ws://127.0.0.1:8080"
End Sub

Private Sub cmdSend_Click()
    m_Client.SendText txtMessage.Text
End Sub

Private Sub cmdDisconnect_Click()
    m_Client.CloseConnection
End Sub

Private Sub m_Client_OnOpen()
    Debug.Print "Connected"
    cmdSend.Enabled = True
End Sub

Private Sub m_Client_OnTextMessage(ByVal Message As String)
    txtLog.Text = txtLog.Text & Message & vbCrLf
End Sub

Private Sub m_Client_OnClose(ByVal Code As WsCloseCode, ByVal Reason As String)
    Debug.Print "Disconnected: " & Reason
    cmdSend.Enabled = False
End Sub

Client with Reconnect

Private WithEvents m_Client As cWebSocketClient
Private m_bAutoReconnect As Boolean
Private m_sServerURL As String

Private Sub Form_Load()
    Set m_Client = New cWebSocketClient
    m_bAutoReconnect = True
    m_sServerURL = "ws://127.0.0.1:8080"
    ConnectToServer
End Sub

Private Sub ConnectToServer()
    If m_Client.State = WS_STATE_CLOSED Then
        Debug.Print "Connecting..."
        m_Client.Connect m_sServerURL
    End If
End Sub

Private Sub m_Client_OnOpen()
    Debug.Print "Connected"
    tmrReconnect.Enabled = False
End Sub

Private Sub m_Client_OnClose(ByVal Code As WsCloseCode, ByVal Reason As String)
    Debug.Print "Connection closed: " & Reason
    
    If m_bAutoReconnect Then
        Debug.Print "Reconnecting in 3 seconds..."
        tmrReconnect.Interval = 3000
        tmrReconnect.Enabled = True
    End If
End Sub

Private Sub tmrReconnect_Timer()
    tmrReconnect.Enabled = False
    ConnectToServer
End Sub

Last Updated: 2026-01-10

cWebSocketClient Class Reference ​

📋 Class Overview ​

📡 Event List ​

🔧 Property Reference ​

State - Connection State ​

URL - Connection URL ​

Host - Server Hostname ​

Port - Server Port ​

AutoPing - Auto Ping ​

PingInterval - Ping Interval ​

🚀 Method Reference ​

Connect - Connect to Server ​

CloseConnection - Close Connection ​

SendText - Send Text Message ​

SendBinary - Send Binary Message ​

SendPing - Send Ping Frame ​

📡 Event Details ​

OnOpen - Connection Opened ​

OnClose - Connection Closed ​

OnTextMessage - Text Message Received ​

OnBinaryMessage - Binary Message Received ​

OnError - Error Occurred ​

OnPong - Pong Received ​

📝 Complete Example ​

Basic Client Example ​

Client with Reconnect ​

cWebSocketClient Class Reference

📋 Class Overview

📡 Event List

🔧 Property Reference

State - Connection State

URL - Connection URL

Host - Server Hostname

Port - Server Port

AutoPing - Auto Ping

PingInterval - Ping Interval

🚀 Method Reference

Connect - Connect to Server

CloseConnection - Close Connection

SendText - Send Text Message

SendBinary - Send Binary Message

SendPing - Send Ping Frame

📡 Event Details

OnOpen - Connection Opened

OnClose - Connection Closed

OnTextMessage - Text Message Received

OnBinaryMessage - Binary Message Received

OnError - Error Occurred

OnPong - Pong Received

📝 Complete Example

Basic Client Example

Client with Reconnect