Halting Application to allow error corrections

I'm using the ErrorHandler control in a sub to check the validity of entries in text boxes. It works just fine. When my sub returns false, meaning that there are errors, I would like to halt the execution of code while the user makes corrections and re-submits the form. This is in a desktop application. I've tried numerous things, but the code keeps executing after the error is returned.

IsValid()
If IsValid() = False Then

... This is where I'd like to stop execution of the trailing code and allow the user to make changes and resubmit the form.

End If

Thanks for the help.
A certified VB.Net Newbie

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Halting Application to allow error corrections

n3bu1a
I think I need to know a little more about the structure of your app . . . Is this happening on a button click What sort of things do you want to happen if the data is valid Tell me about your form and what you mean by "Submit."
S Kaliyan
JacobMVP,

Thanks for the help. I can't believe that I didn't see that. It must be time to go home for the day.
Again, thanks.

Mark F.
BobDaBuilder
Okay, firstly, it's popping the message box twice because of this:

IsValid()
If IsValid() = False Then

The first statement calls your IsValid function. And then it gets called again because you are referencing it in your 'if' condition.

I would simply remove the first call and you should be okay...
EJ Moritz
You're saying it's a desktop application, and since you're on this forum, I guess you're writing a WinForms application. The term "submit" usually means ASP.NET, which might have confused some...

I suggest you take a look at the ErrorProvider. It displays a red ! next to the text box if it's not valid. Here's some sample code:

Private Sub TextBox1_Validation()
  If (... not valid ...) Throw New Exception("Invalid")
End Sub

Private Sub TextBox1_Validating(...) Handles TextBox1.Validating
  Try
    TextBox1_Validation()
  Catch ex As Exception
    ' Validation failed
    e.Cancel = True
    ' Set error provider
    ErrorProvider1.SetError(TextBox1, ex.Message)
  End Try
End Sub

Private Sub TextBox1_Validated(...) Handles TextBox1.Validated
  ' Text box is valid, clear error provider
  ErrorProvider1.SetError(TextBox1, "")
End Sub
Tom Laird-McConnell
My bad,

     I should have included code. Yes, I call the function on a click event. What I've now got is when one of the controls doesn't meet validation the messagebox pops up with the error. When you click on the OK button, the messagebox pops up again. When I click the OK the second time it resets the focus on the first textbox in the form like I want. I've been unable to figure out why the messagebox pops twice.

Private Sub btnPnlLoad_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnPnlLoad.Click

        IsValid()
        If IsValid() = False Then
            txtPlateNum.Focus()
        Else

                  ....... Code to run if IsValid = True

         End if
End Sub

Private Function IsValid() As Boolean

        Dim status As Control

        For Each status In Controls
            If ep1.GetError(status) <> "" Then
                MessageBox.Show("Please correct any errors and resubmit the form", "Data Entry Error", MessageBoxButtons.OK, MessageBoxIcon.Stop)
                Return False
            End If
        Next
              Return True
    End Function

     Again, thanks for the help.

Mark F.

New to VB.net, but having fun
BostonBakedBean
Also, take a look at this show from MSDN TV:

<a href="http://msdn.microsoft.com/msdntv/episode.aspx xml=episodes/en/20030703VSNETBH/manifest.xml">http://msdn.microsoft.com/msdntv/episode.aspx xml=episodes/en/20030703VSNETBH/manifest.xml</a>

The validator shown here saves a lot of code compared to my previous post - couldn't find it before...
Halting Application to allow error corrections

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