Showing an empty textbox using collections

tdpowell23

hi i got a little program working and i want the program to show in a messagebox that there is an empty textbox when you click a button. Unfortunately i can not get it working. Here is the code Private textboxcollection As New Collection Private Sub CollectionsForm_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load textboxcollection.Add(CDsTextbox) textboxcollection.Add(DVDsTextbox) textboxcollection.Add(MP3sTextbox) textboxcollection.Add(JewelCasesTextbox) End Sub Private Sub totallabelclear(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles CDsTextbox.TextChanged, _ DVDsTextbox.TextChanged, MP3sTextbox.TextChanged, JewelCasesTextbox.TextChanged TotalLabel.Text = String.Empty End Sub Private Sub AddButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles AddButton.Click Dim objtextboxes As New TextBox Dim dectotal As Decimal, decsum As Decimal Try For Each objtextboxes In textboxcollection dectotal = objtextboxes.Text decsum += dectotal TotalLabel.Text = decsum Next objtextboxes Catch MessageBox.Show("Each textbox must contain a number" & ControlChars.NewLine & ControlChars.NewLine & "Check the value of " & objtextboxes.Text) End Try End Sub End Class ------- it has to do with the 3rd last line but im really not sure how to fix it any help is appreciated :)

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tdpowell2321y ago
i got it working thanks for the help :)
tdpowell2321y ago
im sorry i havent been specfic about what i need..i will try and figure it out with the answer you gave
MythicalMe21y ago
Not to be demeaning, but when I give an answer, especially for something that is obviously a homework assignment, I am not going to give you the answer you're looking or else I would be doing the assignment for you. If you're stuck, post your question. When you get an answer use it and if it doesn't meet your requirements then you might have to make it to fit. Sometimes that may require a little research. That said; change the exception message in the Throw statement to whatever suits your fancy (see http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vblr7/html/vastmThrow.asp). The message that I put there was for instructive purposes. In the Catch statement you could also look for the exception message with an if...then statement but it seems to me somewhat of a redundancy. What is "it"? I don't understand either. As far as I know, strings are not implicitly converted to numeric and it a very bad habit not to use type conversion.
tdpowell2321y ago
a few things about this i need to show a specific message in the messagebox because its what is required and also it says that objtextboxes can not be converted to decimal which i dont understand
MythicalMe21y ago
In your AddButton_Click event change: TotalLabel.text = decsum to: TotalLabel.text = decsum.ToString("d2") '<== use whatever format you need You're not specifically generating any errors. As written VB will regard whatever is in your textbox as zero so there is nothing to Catch. If you want to use Try... Catch... Finally in that way you'll have rewrite the Click event like this: Try For Each objtextboxes in textboxcollection if objtextboxes.Text = string.empty then Throw New Exception("Empty Textbox") else dectotal = cdec(objtextboxes) decsum += dectotal TotalLabel.Text = decsum.ToString("d2") Next Catch e as Exception MessageBox.Show(e.message) End Try