Although an experienced VBA programmer it is the first time that I make my own classes (objects). I am surprised to see that all properties are 'duplicated' in the Locals Window. A small example (break at 'End Sub'):
' Class module:
Private pName As String
Public Property Let Name(inValue As String)
pName = inValue
End Property
Public Property Get Name() As String
Name = pName
End Property
' Normal module:
Sub Test()
Dim objTest As cTest
Set objTest = New cTest
objTest.Name = "John Doe"
End Sub
Why are both Name
and pName
shown in the Locals Window? Can I in some way get rid of pName
?
As comments & answers already said, that's just the VBE being helpful.
However if you find it noisy to have the private fields and public members listed in the locals toolwindow, there's a way to nicely clean it up - here I put the Test
procedure inside ThisWorkbook
, and left the class named Class1
:
So what's going on here? What's this
?
Here's Class1
:
Option Explicit
Private Type TClass1
Name As String
'...other members...
End Type
Private this As TClass1
Public Property Get Name() As String
Name = this.Name
End Property
Public Property Let Name(ByVal value As String)
this.Name = value
End Property
The class only has 1 private field, a user-defined type value named this
, which holds all the encapsulated data members.
As a result, the properties' underlying fields are effectively hidden, or rather, they're all regrouped under this
, so you won't see the underlying field values unless you want to see them:
And as an additional benefit, you don't need any pseudo-Hungarian prefixes anymore, the properties' implementations are crystal-clear, and best of all the properties have the exact same identifier name as their backing field.