[VB 2008] Potrebna pomoc za razumjevanje koda
 

Posto nisam neki expert za VB dosao sam ovamo da trazim pomoc od vas, nadam se da ce te me razumjeti.
Potrebno mi je objasnjenje koda za kalkulator u Visual basicu 2008 za skolski zadatak.Znaci sve kako sta radi po mogucnosti.

Kod koji se odnosi na broj:

If bHasFirstNumber Then
If dNumber <> 0 Then
If Me.TextBox1.Text = 0 Then
Me.TextBox1.Text = 1
bHasSecondNumber = True

Exit Sub
End If

Me.TextBox1.Text &= 1
Exit Sub
End If
Me.TextBox1.Text &= 1
Else
Me.TextBox1.Text = 1
bHasFirstNumber = True
bHasOperation = False
End If
End Sub

Kod koji se odnosi na opciju C:

Me.TextBox1.Text = 0
dNumber = 0
bHasFirstNumber = False
bHasSecondNumber = False
bHasOperation = False
sOperation = ""
End Sub

Kod koji se odnosi na +:

If bHasSecondNumber Then
If bHasOperation Then
If (sOperation = "+") Then
dNumber = Val(Me.TextBox1.Text) + dNumber
ElseIf (sOperation = "-") Then
dNumber = dNumber - Val(Me.TextBox1.Text)
ElseIf (sOperation = "*") Then
dNumber = Val(Me.TextBox1.Text) * dNumber
ElseIf (sOperation = "/") Then
dNumber = dNumber / Val(Me.TextBox1.Text)
Else
Exit Sub
End If
sOperation = "+"
bHasSecondNumber = False
Me.TextBox1.Text = 0
Exit Sub
Else
sOperation = "+"
dNumber = dNumber + Val(Me.TextBox1.Text)
bHasSecondNumber = False
Me.TextBox1.Text = 0
Exit Sub
End If
End If
If bHasFirstNumber Or bHasOperation Then
If bHasOperation Then
bHasFirstNumber = True
End If
sOperation = "+"
dNumber = Val(Me.TextBox1.Text)
Me.TextBox1.Text = 0
End If
End Sub