Breuk: de code van de klasse

• De locale variabelen
  'local variable(s) to hold property value(s)
  Private mvarTeller As Integer 'local copy
  Private mvarNoemer As Integer 'local copy
  Private mvarWaarde As Currency 'local copy
• De eigenschappen lezen en instellen
  Public Property Let Waarde(ByVal vData As Currency)
  'used when assigning a value to the property, on the left side of an assignment.
  'Syntax: X.Waarde = 5
  'Mag niet rechtstreeks gebeuren
  'mvarWaarde = vData
  End Property
  
  Public Property Get Waarde() As Currency
  'used when retrieving value of a property, on the right side of an assignment.
  'Syntax: Debug.Print X.Waarde
  mvarWaarde = mvarTeller / mvarNoemer
  Waarde = mvarWaarde
  End Property
  
  Public Property Let noemer(ByVal vData As Integer)
  'used when assigning a value to the property, on the left side of an assignment.
  'Syntax: X.Noemer = 5
  If vData = 0 Then
  'noemer mag niet nul zijn
  Err.Raise 1001, , "Noemer mag niet nul zijn"
  Exit Property
  End If
  mvarNoemer = vData
  End Property
  
  Public Property Get noemer() As Integer
  'used when retrieving value of a property, on the right side of an assignment.
  'Syntax: Debug.Print X.Noemer
  vereenvoudig
  noemer = mvarNoemer
  End Property
  
  Public Property Let teller(ByVal vData As Integer)
  'used when assigning a value to the property, on the left side of an assignment.
  'Syntax: X.Teller = 5
  mvarTeller = vData
  End Property
  
  Public Property Get teller() As Integer
  'used when retrieving value of a property, on the right side of an assignment.
  'Syntax: Debug.Print X.Teller
  vereenvoudig
  teller = mvarTeller
  End Property
• Om te kunnen vereenvoudigen, hebben we een paar hulpfuncties nodig: het kleinste van twee getallen, en ed grootste gemene deler van twee getallen.
  Function min(g1 As Integer, g2 As Integer) As Integer
  If g1 < g2 Then
  min = g1
  Else
  min = g2
  End If
  End Function
  
  Function ggd(g1 As Integer, g2 As Integer) As Integer
  Dim test As Integer
  For test = min(g1, g2) To 1 Step -1
  If g1 Mod test = 0 And g2 Mod test = 0 Then
  ggd = test
  Exit Function
  End If
  Next test
  End Function
  
• Vereenvoudigen kunnen we dan zo doen:
  Private Sub vereenvoudig()
  Dim deler As Integer
  deler = ggd(mvarTeller, mvarNoemer)
  mvarTeller = mvarTeller / deler
  mvarNoemer = mvarNoemer / deler
  End Sub
• De bewerkingen op de breuken zien er zo uit:
  Public Sub TelBreukOp(br As Breuk)
  mvarTeller = mvarTeller * br.noemer + br.teller * mvarNoemer
  mvarNoemer = mvarNoemer + br.noemer
  End Sub
  
  Public Sub Telop(getal As Integer)
  mvarTeller = mvarTeller + getal * mvarNoemer
  End Sub
  
  
  Public Sub Vermenigvuldig(factor As Integer)
  mvarTeller = mvarTeller * factor
  End Sub
  
  Public Sub Deel(deler As Integer)
  'niet delen door nul
  If deler = 0 Then
  Err.Raise 11
  Exit Sub
  End If
  mvarNoemer = mvarNoemer * deler
  End Sub

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