Comments by Member 10701701 (Top 17 by date)

Hi this is the complete code that draws a temperature display. I only put the relevant part in my first post.
Regards Nevjc


Imports System.Drawing.Drawing2D
Imports System.IO.Ports

Public Class Form1
Dim bmp As Bitmap = New Bitmap(100, 600)
Dim temperature1 As Double = 10
Dim WithEvents sp As New SerialPort


Private Sub picTherm_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles picTherm.Paint
Dim g As Graphics = Graphics.FromImage(bmp)
g.Clear(Color.White)
' fill temperature
If temperature1 > 100 Then temperature1 = 100
If temperature1 < 0 Then temperature1 = 0
g.FillRectangle(Brushes.Red, 48, 550 - CInt(temperature1 * 5), 4, CInt(temperature1 * 5))
'draw scale
g.DrawLine(Pens.Black, 45, 550, 45, 50)
' minor ticks
For i As Integer = 50 To 550 Step 5
g.DrawLine(Pens.Black, 45, i, 48, i)
Next
'major ticks
Dim f As Font = New Font("Verdana", 8, FontStyle.Regular)
Dim scale As Integer
For i As Integer = 550 To 50 Step -25
g.DrawLine(Pens.Black, 45, i, 55, i)
scale = (550 - i) / 5
g.DrawString(Str(scale), f, Brushes.Black, 10, i - 8)
Next
picTherm.Image = bmp
End Sub




Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

End Sub

Private Sub Panel1_Paint(ByVal sender As System.Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Panel1.Paint

End Sub

Private Sub btnConnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnConnect.Click
Try
sp.BaudRate = "9600"
sp.PortName = "COM5"
sp.Open()
If sp.IsOpen Then
btnConnect.Visible = False
btnDisconnect.Visible = True
End If
Catch
sp.Close()
End Try
End Sub


Private Sub btnDisconnect_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnDisconnect.Click
Try
sp.Close()
btnConnect.Visible = True
btnDisconnect.Visible = False
Exit Sub
Catch
MessageBox.Show("Some kind of problem.")
End Try

End Sub

Private Sub Form1_FormClosing(ByVal sender As System.Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles MyBase.FormClosing
If sp.IsOpen() Then
MessageBox.Show("Disconnect before closing")
e.Cancel = True
End If

End Sub
Delegate Sub myMethodDelegate(ByVal text As String)
Dim myDelegate As New myMethodDelegate(AddressOf ProcessReading)

Private Sub SerialPort_DataReceived(ByVal sender As Object, ByVal e As System.IO.Ports.SerialDataReceivedEventArgs) Handles sp.DataReceived
Dim str As String = sp.ReadLine()
Invoke(myDelegate, Str)

End Sub
Sub ProcessReading(ByVal input As String)
If IsNumeric(Input) Then
temperature1 = CDbl(input)
picTherm.Refresh()
Label1.Text = CDbl(input)
Label2.Text = CDbl(input) * 2
Label3.Text = CDbl(input) / 2
End If
End Sub
End Class