Control looping.

[BrailleSchool]

Hi all,

I am trying to do something and not able to get to where I need to go. I have 12 checkboxes on a form. 4 for "And", 4 for "Or" and 4 for "Exclude".

I am trying to check to see if all checkboxes that contain the word "Exclude" in the control name are checked. If they are ALL checked, to show a messagebox. I am getting there but when I try to loop through the controls to check the name, I am getting a blue line under the code that says:

Class 'System.Windows.Form.Control' cannot be indexed because it has no default property.

Screenshots attached.

[BrailleSchool]

Ok, I have tried the following and the messagebox comes up when I go to make a different selection other than what is default on form load. Hmmm.

<CLSCompliant(True)> Private Sub DisallowAllExclude()
        Dim CheckBoxArr() As Elegant.Ui.CheckBox = {chkResolutionTypeExclude, _
                                                    chkDateToFromExclude, _
                                                    chkClientNameExclude, _
                                                    chkClientPhoneNumberExclude}
 
        Dim CheckBoxArr2() As Elegant.Ui.CheckBox = {chkResolutionTypeAnd, _
                                                     chkDateToFromAnd, _
                                                     chkClientNameAnd, _
                                                     chkClientPhoneNumberAnd}
 
        For Each chk As Elegant.Ui.CheckBox In CheckBoxArr
            If chk.CheckState = CheckState.Checked Then
                If MessageBox.Show("You cannot exclude all options when trying to search.  Please modify your selection and try again.", _
                                   "Exclusion Issue Encountered", _
                                   MessageBoxButtons.OK, _
                                   MessageBoxIcon.Exclamation, _
                                   MessageBoxDefaultButton.Button1, _
                                   MessageBoxOptions.DefaultDesktopOnly, False) = Windows.Forms.DialogResult.OK Then
 
                    'Check all the And checkboxes.
                    For Each chk2 As Elegant.Ui.CheckBox In CheckBoxArr2
                        chk2.CheckState = CheckState.Checked
                    Next chk2
                Else 'Do nothing
                    '
                End If
            End If
        Next chk
    End Sub

[.paul.]

here's an example using vb2005 + standard checkboxes:

Public Class Form1
 
    Dim CheckBoxArr() As CheckBox
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        CheckBoxArr = New CheckBox() {chkResolutionTypeExclude, _
                                                    chkDateToFromExclude, _
                                                    chkClientNameExclude, _
                                                    chkClientPhoneNumberExclude}
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MsgBox(Array.FindAll(CheckBoxArr, AddressOf isChecked).Length)
    End Sub
 
    Private Function isChecked(ByVal cb As CheckBox) As Boolean
        Return cb.Checked
    End Function
 
End Class

this is how i'd do it in vb2008:

Public Class Form1
 
    Dim CheckBoxArr() As CheckBox
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        CheckBoxArr = New CheckBox() {chkResolutionTypeExclude, _
                                                    chkDateToFromExclude, _
                                                    chkClientNameExclude, _
                                                    chkClientPhoneNumberExclude}
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MsgBox(CheckBoxArr.Count(Function(cb) cb.Checked))
    End Sub
 
End Class

[Bruce Fox]

How about ...:

If GrandChildControl.name.Contains("Exclude") Then
 
Dim cb = Directcast(GrandCHildControl, Elegant.Ui.CheckBox)
If cb.Checked = CheckedState.Checked Then...
 
End If
 
End If

Or

If GrandChildControl.name.Contains("Exclude") Then
 
If Directcast(GrandCHildControl, Elegant.Ui.CheckBox).Checked = CheckedState.Checked Then ...
 
End If
 
End If

Syntax may be off as I typed it in NotePad.

Note, you don't need an index as you already iterating the CheckBox's named Exclude, and in this case there would br four.

[BrailleSchool]

here's an example using vb2005 + standard checkboxes:

Public Class Form1
 
    Dim CheckBoxArr() As CheckBox
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        CheckBoxArr = New CheckBox() {chkResolutionTypeExclude, _
                                                    chkDateToFromExclude, _
                                                    chkClientNameExclude, _
                                                    chkClientPhoneNumberExclude}
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MsgBox(Array.FindAll(CheckBoxArr, AddressOf isChecked).Length)
    End Sub
 
    Private Function isChecked(ByVal cb As CheckBox) As Boolean
        Return cb.Checked
    End Function
 
End Class

this is how i'd do it in vb2008:

Public Class Form1
 
    Dim CheckBoxArr() As CheckBox
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        CheckBoxArr = New CheckBox() {chkResolutionTypeExclude, _
                                                    chkDateToFromExclude, _
                                                    chkClientNameExclude, _
                                                    chkClientPhoneNumberExclude}
 
    End Sub
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
        MsgBox(CheckBoxArr.Count(Function(cb) cb.Checked))
    End Sub
 
End Class

I tried that too and I got the following error.

[.paul.]

you declared ExcludeArr as a variable + not an array. try this:

Dim ExcludeArr() as Elegant.UI.Checkbox

[BrailleSchool]

How about ...:

If GrandChildControl.name.Contains("Exclude") Then
 
Dim cb = Directcast(GrandCHildControl, Elegant.Ui.CheckBox)
If cb.Checked = CheckedState.Checked Then...
 
End If
 
End If

Or

If GrandChildControl.name.Contains("Exclude") Then
 
If Directcast(GrandCHildControl, Elegant.Ui.CheckBox).Checked = CheckedState.Checked Then ...
 
End If
 
End If

Syntax may be off as I typed it in NotePad.

Note, you don't need an index as you already iterating the CheckBox's named Exclude, and in this case there would br four.

I had tried that too before posting the thread. This doesnt work because as soon as I check one checkbox for Exclude, the messagebox comes up.

[BrailleSchool]

Ok, I tried Pauls code and I am not getting far right now. Screen shots attached.

[.paul.]

the length property of an array is an integer property + you need to test it is = 4 to test if all your checkboxes are checked:

if Array.FindAll(ArrExclude, AddressOf isChecked).length = 4 then
...

[stanav]

Try this:

    Private excludeCheckBoxes() As Elegant.Ui.CheckBox = Nothing

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.excludeCheckBoxes = New Elegant.Ui.CheckBox() {chkResolutionTypeExclude, _
                                                                                 chkDateToFromExclude, _
                                                                                 chkClientNameExclude, _
                                                                                 chkClientPhoneNumberExclude}

    End Sub

    Private Function AreAllExcludeCheckBoxesChecked() As Boolean
          Dim result As Boolean = True
          For Each chkBox As Elegant.Ui.CheckBox In Me.excludeCheckBoxes
               If chkBox.Checked = False Then
                     result = False
                     Exit For
               End If
          Next
          Return result
    End Function

   <CLSCompliant(True)> Private Sub DisallowAllExclude()
          If Me.AreAllExcludeCheckBoxesChecked() = True Then
                MessageBox.Show("Hey, you can't exclude every options like that.")
          End If
   End Sub

[BrailleSchool]

I did a messagebox to show the value and verified is 0 for false and 1 for true. I still get the same error when doing:

If Array.FindAll(ArrExclude, AddressOf isChecked).Length = 1 Then

hm!

[BrailleSchool]

the length property of an array is an integer property + you need to test it is = 4 to test if all your checkboxes are checked:

if Array.FindAll(ArrExclude, AddressOf isChecked).length = 4 then
...

i tried that too to see what happens and i got an InvalidOperationException.

[BrailleSchool]

Try this:

    Private excludeCheckBoxes() As Elegant.Ui.CheckBox = Nothing

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Me.excludeCheckBoxes = New Elegant.Ui.CheckBox() {chkResolutionTypeExclude, _
                                                                                 chkDateToFromExclude, _
                                                                                 chkClientNameExclude, _
                                                                                 chkClientPhoneNumberExclude}

    End Sub

    Private Function AreAllExcludeCheckBoxesChecked() As Boolean
          Dim result As Boolean = True
          For Each chkBox As Elegant.Ui.CheckBox In Me.excludeCheckBoxes
               If chkBox.Checked = False Then
                     result = False
                     Exit For
               End If
          Next
          Return result
    End Function

   <CLSCompliant(True)> Private Sub DisallowAllExclude()
          If Me.AreAllExcludeCheckBoxesChecked() = True Then
                MessageBox.Show("Hey, you can't exclude every options like that.")
          End If
   End Sub

Invalid Operation Exception. Frustrating. I can get it to work without an issue when using an If block but I am sure there is an easier way of doing this.

[.paul.]

what sort of size is your project? could you upload it (remove any confidential information)?

[stanav]

The last error you got is a null reference exception. Do you know which line in your code that it causes it?
The code I posted will not cause it provided that you have the checkboxes as named on your form. And If you don't, it won't compile and thus you can't get an exception from it.

[BrailleSchool]

Those errors happen when I launch the form in run-time via the button. If I remove Pauls code or comment it out, the form loads without error.

[BrailleSchool]

what sort of size is your project? could you upload it (remove any confidential information)?

The whole folder is 98.3MB in size.

[BrailleSchool]

The last error you got is a null reference exception. Do you know which line in your code that it causes it?
The code I posted will not cause it provided that you have the checkboxes as named on your form. And If you don't, it won't compile and thus you can't get an exception from it.

The control names are correct. I made sure of it and double checked. The error happens on the loading of the form in the button click event.

[BrailleSchool]

what sort of size is your project? could you upload it (remove any confidential information)?

i am about to send you a PM with the URL i uploaded the project to. i am using two custom controls on the forms so you will need to install them. ill explain more in the PM.

[.paul.]

ok...

[dminder]

Here is my go at it, I have used this type of loop before and it has worked very well for me (well enough that I include a more enhanced variation of it with my base dll in all projects):

 Private Function All_Exclude_checked(ByVal ctrl As Control) As Boolean
        'the thought process behind this is to send your panel containing the controls
        ' in as the initial control and allow this to loop. If there are any sub controls
        ' then they are handled with the loop below. Otherwise, it will check the control
        ' itself. if it is the type of control you are looking for then check the text. If
        ' the text is NOT "Excluded" then return false. This would mean that if ANY other
        ' checkbox was marked then it would return false.
        If CType(ctrl, Control).HasChildren = True Then
            For Each child As Control In ctrl.Controls
                All_Exclude_checked(child)
            Next
        End If

        If TypeOf ctrl Is CheckBox Then
            If CType(ctrl, CheckBox).Text <> "Excluded" Then
                Return False
            Else
                Return True
            End If
        End If
    End Function

Hope that this helps some!

D

[dminder]

After looking back over the code, I noticed that I REALLY messed up on it. Here is a revised version that works - with checkboxes anyways!!

 Private trigger As Boolean = True

    Private Function All_Exclude_checked(ByVal ctrl As Control) As Boolean
        If CType(ctrl, Control).HasChildren = True Then
            For Each child As Control In ctrl.Controls
                All_Exclude_checked(child)
            Next
        ElseIf TypeOf ctrl Is CheckBox Then
            If CType(ctrl, CheckBox).Checked = True Then
                If CType(ctrl, CheckBox).Text <> "Excluded" Then
                    trigger = False
                End If
            End If
        End If
        Return trigger
    End Function

I am using an external variable to keep track of whether another box was checked. Be SURE to reset that variable (trigger) BEFORE you run it again because it will retain the last value it was set to!!!

Again, sorry for the sloppiness - I really need to watch when I am copying and pasting and trimming stuff down!!!

D

[BrailleSchool]

OK, I am using FxCop from Microsoft to scan my built exe and it is giving me an error. It is saying:

'Ctrl', a parameter, is cast to type 'CheckBox' multiple times in method 'FrmRecords.AllExcludedChecked(Control)'. Cache the result of the 'as' operator or direct cast in order to eliminate the redundant isint instruction."

It is giving this URL as a help topic.

So as per the topic suggested, I went into my code and changed it to the following and it still says the same thing when I rebuild the project and scan it with FxCop.

<CLSCompliant(True)> Private Function AllExcludedChecked(ByVal Ctrl As Control) As Boolean
        Dim Chk As Elegant.Ui.CheckBox = DirectCast(Ctrl, Elegant.Ui.CheckBox)
 
        If Ctrl.HasChildren = True Then
            For Each Child As Control In Ctrl.Controls
                AllExcludedChecked(Child)
            Next Child
        ElseIf TypeOf Ctrl Is Elegant.Ui.CheckBox Then
            If Chk.Checked = True Then
                If Chk.Text = "Exclude" Then
                    Trigger = True
                Else
                    Trigger = False
                End If
            End If
        End If
 
        Return Trigger
    End Function

Any ideas?

[dbasnett]

Something to think about...

Public Class Form1

    Dim ctlDict As New Dictionary(Of String, Control)

    Private Sub Form1_Load(ByVal sender As System.Object, _
                           ByVal e As System.EventArgs) Handles MyBase.Load

        'build a dictionary of all controls
        Dim ctl As Control = Me.GetNextControl(Me, True) 'Get the first control in the tab order.
        Do Until ctl Is Nothing
            ctlDict.Add(ctl.Name, ctl)
            ctl = Me.GetNextControl(ctl, True) 'Get the next control in the tab order.
        Loop
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, _
                              ByVal e As System.EventArgs) Handles Button1.Click
        'query the dictionary of controls
        Dim foo As IEnumerable(Of Generic.KeyValuePair(Of String, Control))
        foo = From de In ctlDict _
              Where de.Key.Contains("Exclude") AndAlso _
              TypeOf de.Value Is CheckBox AndAlso _
              CType(de.Value, CheckBox).Checked Select de

        'the count
        Debug.WriteLine(foo.Count.ToString)
    End Sub
End Class

[BrailleSchool]

thanks, ill check it out.

Something to think about...

Public Class Form1

    Dim ctlDict As New Dictionary(Of String, Control)

    Private Sub Form1_Load(ByVal sender As System.Object, _
                           ByVal e As System.EventArgs) Handles MyBase.Load

        'build a dictionary of all controls
        Dim ctl As Control = Me.GetNextControl(Me, True) 'Get the first control in the tab order.
        Do Until ctl Is Nothing
            ctlDict.Add(ctl.Name, ctl)
            ctl = Me.GetNextControl(ctl, True) 'Get the next control in the tab order.
        Loop
    End Sub


    Private Sub Button1_Click(ByVal sender As System.Object, _
                              ByVal e As System.EventArgs) Handles Button1.Click
        'query the dictionary of controls
        Dim foo As IEnumerable(Of Generic.KeyValuePair(Of String, Control))
        foo = From de In ctlDict _
              Where de.Key.Contains("Exclude") AndAlso _
              TypeOf de.Value Is CheckBox AndAlso _
              CType(de.Value, CheckBox).Checked Select de

        'the count
        Debug.WriteLine(foo.Count.ToString)
    End Sub
End Class