VBMAN Network Data Display Example

Overview

This example demonstrates how to use the VBMAN framework to implement real-time network data display, including data collection, transmission, parsing, and visualization features.

Project Structure

NetDataShow/
  ├── Form1.frm        # Main form, contains data display interface
  ├── Form1.frx        # Form resource file
  ├── NetDataShow.vbp  # Project file
  └── _pic/           # Image resource directory

Core Code Analysis

1. Data Display Form (Form1.frm)

'Data display form
Private WithEvents NetClient As New cTcpClient
Private WithEvents Timer1 As New Timer

Private Sub Form_Load()
    'Connect to data server
    With NetClient
        .Connect "127.0.0.1", 9000
    End With
    
    'Start periodic refresh
    With Timer1
        .Interval = 1000
        .Enabled = True
    End With
End Sub

'Data reception handling
Private Sub NetClient_OnDataArrival()
    Dim data As String
    data = NetClient.RecvText
    
    'Parse data
    ParseData data
    
    'Update display
    UpdateDisplay
End Sub

'Periodic refresh handling
Private Sub Timer1_Timer()
    'Get latest data
    NetClient.Send "GET_DATA"
End Sub

'Data parsing
Private Sub ParseData(data As String)
    With VBMAN.Json
        If .Decode(data) Then
            'Parse temperature data
            txtTemp.Text = .Item("temperature")
            
            'Parse humidity data
            txtHumidity.Text = .Item("humidity")
            
            'Update trend chart
            UpdateChart .Item("history")
        End If
    End With
End Sub

2. Chart Display Implementation

'Update trend chart display
Private Sub UpdateChart(history As Object)
    'Clear old data
    Chart1.Clear
    
    'Add new data points
    For Each point In history
        Chart1.AddPoint point("time"), point("value")
    Next
    
    'Refresh display
    Chart1.Refresh
End Sub

'Custom display format
Private Sub FormatDisplay()
    'Set value format
    txtTemp.Format = "0.00 ℃"
    txtHumidity.Format = "0.0 %"
    
    'Set alarm thresholds
    txtTemp.AlarmValue = 30
    txtHumidity.AlarmValue = 85
    
    'Configure chart style
    With Chart1
        .Title = "Temperature Trend"
        .XLabel = "Time"
        .YLabel = "Temperature(℃)"
        .GridVisible = True
        .Refresh
    End With
End Sub

Feature Description

1. Data Collection Features

   • Network communication
   • Data parsing
   • Real-time updates
   • Periodic refresh

2. Data Display

   • Numerical display
   • Trend charts
   • Alarm notifications
   • Automatic refresh

3. User Interface

   • Layout design
   • Interactive control
   • Display formatting
   • Theme styling

Technical Points

1. TCP communication implementation
2. JSON data processing
3. Chart control application
4. Interface refresh mechanism

Use Cases

1. Industrial monitoring
2. Environmental monitoring
3. Equipment status monitoring
4. Data visualization

Extension Suggestions

1. Add data recording
2. Implement multi-channel display
3. Add data analysis
4. Support report export
5. Optimize refresh mechanism