[RESOLVED] Sum Listbox

[toecutter]

I have tried both of these to sum a listbox's entries

        Dim number As Integer = Me.lstBracingLengths.Items.Count - 1
        Dim y As Integer
        Dim totall As Integer
        For y = 0 To number
            totall = totall + Convert.ToInt16(Me.lstBracingLengths.Items.Item(y))
        Next y
        Me.txtBracingTotals.Text = Convert.ToString(totall)

        Dim totall As Integer
        For Each item As Integer In lstBracingLengths.Items
            totall += item
        Next
        txtBracingTotals.Text = totall

Both work but they round the values up for some reason i cannot see.
see picture


I am using a round up formula before the entries are placed in the listbox but i cannot see that causing it

        Dim wl As Double = Me.txtWallLength.Text
        Dim wh As Double = Me.cmbWallHeight.Text
        Dim sqr1 As Double = wl * wl
        Dim sqr2 As Double = wh * wh
        Dim Total As Double = sqr1 + sqr2
        Dim sqrTotal As Double = Math.Sqrt(Total)
        'populates listbox with bracing lengths
        Me.lstBracingLengths.Items.Add(Math.Round(sqrTotal, 3))

regards
toe

[kebo]

tis because Convert.ToInt16(5.564) = 6
kevin

[toecutter]

tis because Convert.ToInt16(5.564) = 6
kevin

thanks for the quick reply kebo.
It also happins when using the 2nd block of code which dosnt have Convert.ToInt16?
regards
toe

[kebo]

yea...its because you are converting to a integer still

For Each item As Integer In lstBracingLengths.Items

BTW....you don't seem to have Option Strict turned on...if you did you wouldn't be able to run that line of code you did because you are turning ListBoxItems into integer

try this

For Each Item as ListViewItem in lstBracingLengths.Items
     totall += CType(item.Text, Double)
Next
txtBracingTotals.Text = totall

kevin

[jmcilhinney]

Did you add Double values to the ListBox in the first place? If so then this:

Dim totall As Integer
        For Each item As Integer In lstBracingLengths.Items
            totall += item
        Next
        txtBracingTotals.Text = totall

is the most appropriate way to do it but, as kebo said, if you cast as type Integer then of course the fractional parts will be rounded. It should be:

Dim totall As Double
        For Each item As Double In lstBracingLengths.Items
            totall += item
        Next
        txtBracingTotals.Text = totall

[toecutter]

Thanks Guys.
Did you add Double values to the ListBox in the first place? Yes, values as in the listbox picture above using this code

        Dim wl As Double = Me.txtWallLength.Text
        Dim wh As Double = Me.cmbWallHeight.Text
        Dim sqr1 As Double = wl * wl
        Dim sqr2 As Double = wh * wh
        Dim Total As Double = sqr1 + sqr2
        Dim sqrTotal As Double = Math.Sqrt(Total)
        'populates listbox with bracing lengths
        Me.lstBracingLengths.Items.Add(Math.Round(sqrTotal, 3))

Your second code works correctly jmcilhinney

        Dim totall As Double
        For Each item As Double In lstBracingLengths.Items
            totall += item
        Next
        txtBracingTotals.Text = totall

Option Explicit was on kevin.

I really appreciate your effort in helping me.
regards
toe

[joel_wylde]

im new here, i had this same problem and this has help me a lot thank you very much