VB.net Decimal value of Binair checkbox

Question

I have 8 checkboxes in a group and I want to have the decimal value for binair basicly if

checkbox1.checked = true checkbox2.checked = true

then the value has to be (2 ^ 0) + (2 ^ 1) = 3 (the 0 = checkbox1 and the 1 = checkbox2 etc.)

I know the solution could be simple but until now I just can't get it working. The code I have right now is the following:

    Private Function AnyOptionsChecked() As Boolean
    For Each chk As CheckBox In GroupBox1.Controls
        t = t + 1
        If chk.Checked = True Then
            i = i + 2 ^ t
        End If
    Next
    Return False
End Function

but it seems like t is already at 7 (cause there are 8 checkboxes) before the if/else starts working.

Does someone knows how to solve this problem or is able to point me in the right direction? Thanks.

Answer 1

Your function is returning a boolean (true/false), but really you want to be returning a number if you want to know what options have been checked. How about this:

Private Function OptionsChecked() As Integer
    Dim t As Integer = 0
    Dim result As Integer = 0
    For Each chk As CheckBox In GroupBox1.Controls
        If chk.Checked = True Then
            result = result + 2 ^ t
        End If
        t = t + 1
    Next
    Return result
End Function

So my function returns zero when no options are checked. Otherwise it returns an integer indicating which options have been checked (1 = the first option, 2 = second option, 3 = the first and second option, etc.).