How to differentiate ByVal and ByRef [RESOLVED]

[jeremy_ckw]

Hi all,

I'm a bit confused by these by value and by reference. Can anyone show me an example of using this two? I can't differentiate them.

For example, is the following call byref or byval?

Private sub Form_Load
dim blnCorrect as boolean
 
    call TrueOrFalse(blnCorrect)
    if blnCorrect = True then
           msgbox "True"
    else
           msgbox "False"
    end if
End Sub
 
Private sub Passing(a as boolean)
    .....
    .....
    a = Not a
End Sub

Please advice.

Regards,
Jeremy