garyelmer

I'm enrolled in VB.net at a local community college. We're using Visual Basic 2005 Text Book.

My assignment is to create a form that does several things which was easy until I came to this part . . .

Add the contents of the ListBox and show the total in a label.

If there were only 2 items it would be easy, but there is a varying number of items.

Chapter 5 also deals with loops so I'm thinking of using a For . . .Next loop.

I can get the number of items in the list box into a label but I am REALLY stuck on totalling all the numbers in the list box.

Example:

In lstTotals there are 5 items in lstCosts

250
525
375
600
125


and here is what I have so far, which isn't working:

intListSize = lstCosts.Items.Count - 1


For intCount = 0 To intListSize
decTotalCosts = lstCosts.Items(intCount)
intCount += 1

Next intCount

lblTotalCost.Text = decTotalCosts


What am I missing here?

Thank you in advance.

Wizard1988

You are not totaling decTotalCost you simply reasign the last value of lstCost.ITems(intCount)

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JG-Webdesign

garyelmer

I know, it isn't working.

My question is how do you total a bunch of values in a listbox using a for . . next loop.

Wizard1988

change:
decTotalCosts = lstCosts.Items(intCount)

to:
decTotalCosts += lstCosts.Items(intCount)

if you don't know what the += operator does you can use this

decTotalCost = decTotalCost + lstCost.Items(intCount)

__________________
JG-Webdesign

garyelmer

Okay, I did that and here is what I have so far . . .

intListSize = lstCosts.Items.Count - 1


For intCount = 0 To intListSize
decTotalCosts += lstCosts.Items(intCount)
intCount += 1

Next intCount

lblTotalCost.Text = decTotalCosts


What it is doing now is adding item 0, 2, 4 and so on.
It is skipping 1, 3, 5 etc.

DaWei

That's because you're incrementing intCount twice per loop. Read about what "Next" does....

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garyelmer

Oh well,

I've been working on this one for way too long.
Maybe the answer will come to me in a dream.

Thank you for your help.

Good night.

garyelmer

Hey Mr. Wei,

Thank you for that post.

Based on what you said I simply deleted: intCount = intCount + 1
and all is good. I am a total newbie at this stuff and I don't really
understand why it's working it just is.

I will study it more tomorrow.

Good Night!

Zzzzzzzzzzzzzzzzzzzzzz

lectricpharaoh

Code tags.

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