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How to modify label.text in a dynamically generated label in VB.netobjects in VB2005. Can someone please help? In a nutshell: My app creates an equal number of checkboxes and labels that share the same Tag number. (I thought it might help) The checkboxes name is a concatenation of "chkCancel" and a number that represents the order in which they were created: chkCancel0 (Tag = 0) chkCancel1 (Tag = 1) chkCancel2 (Tag = 2) etc... The same goes for the labels lblLabel0 (Tag = 0) lblLabel1 (Tag = 1) lblLabel2 (Tag = 2) etc... When the label is created, its text property is given a value (lblLabel.text = value). What I want to do, is clear that text property when I click on the corresponding checkbox. I want to do it with a common sub, handler, whatever, that will work for all checkboxes. My problem is how to acces the label text property of a dynamically created label. Pseudo code: lableTag = sender.tag if sender.checked=true then lblLabel(labelTag).text="" (this is the part I have trouble with) I don't seem to be able to reference any object created dynamically... It must be very simple for an experienced programmer, but not to vbnewbie... and it is driving me nuts! Thanks Your event handler will go something like this:
Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal e As EventArgs) Dim _tag As Object = CType(sender, Control).Tag If _tag IsNot Nothing Then Dim _c As Control = FindControl(Me, GetType(Label), _tag) If _c IsNot Nothing Then CType(_c, Label).Text = String.Empty End If End Sub Private Function FindControl(ByVal start As Control, ByVal type as Type, tag As Object) As Control For Each _c as Control In start.Controls If _c.GetType() Is type Then If _c.Tag IsNot Nothing AndAlso _c.Tag = tag Then Return _c Else If _c.HasChildren Then Dim _cc As Control = FindControl(_c, type, tag) If _cc IsNot Nothing Then Return _cc End If End If Next Return Nothing End Function When you 'dynamically generate' your CheckBox controls, subscribe to the event handler with something like: AddHandler chkCancel0.CheckChanged, AddressOf DynamicCheckBox_CheckChanged AddHandler chkCancel1.CheckChanged, AddressOf DynamicCheckBox_CheckChanged etc. Note that the same handler is used. Note also that the event handler does not have a Handles clause. When any one of you dynamic CheckBoxes is clicked, the event handler is called and sender is a reference to the CheckBox that was clicked. We then attempt to get a reference to a Label control anywhere on the form that has a matching Tag property. If we get one then we set it's Text Property to an empty string. Let us konw how you get on. Show quoteHide quote "vbnewbie" <biol***@gmail.com> wrote in message news:1167466759.111733.270610@n51g2000cwc.googlegroups.com... >I am having problems accessing properties of dynamically generated > objects in VB2005. Can someone please help? > In a nutshell: > My app creates an equal number of checkboxes and labels that share the > same Tag number. (I thought it might help) > The checkboxes name is a concatenation of "chkCancel" and a number that > > represents the order in which they were created: > chkCancel0 (Tag = 0) > chkCancel1 (Tag = 1) > chkCancel2 (Tag = 2) > etc... > > The same goes for the labels > > > lblLabel0 (Tag = 0) > lblLabel1 (Tag = 1) > lblLabel2 (Tag = 2) > etc... > > > When the label is created, its text property is given a value > (lblLabel.text = value). > > > What I want to do, is clear that text property when I click on the > corresponding checkbox. > I want to do it with a common sub, handler, whatever, that will work > for all checkboxes. > My problem is how to acces the label text property of a dynamically > created label. > > > Pseudo code: > > > lableTag = sender.tag > if sender.checked=true then > lblLabel(labelTag).text="" (this is the part I have trouble with) > > I don't seem to be able to reference any object created dynamically... > > > It must be very simple for an experienced programmer, but not to > vbnewbie... and it is driving me nuts! > Thanks > mediocrevbprogrammer.freed 's code WOULD work if the controls were
created at design time. Since they are not, I get an error because the label have not been declared (How could I declare them since they don't exist!) What would be nice is to have some type of code that would let me modify or get a value from a control property such as: tag as a variable (0, 1,2, etc) lblLabel(tag).Text="" This is something very usfull in VBA The other part that does not work in mediocrevbprogrammer.freed 's is the fact the number of labels that can be created in my app is limitless. Which means I would need to be able to modify the number of Cases, or get rid of the Case-End Case all together in favor of a variable appended to the control name: lblLabel name = lblLabel(tag number). Is that at all possible? Stephany's code worked practically out of the box! Thanks! A few questions, though. I am not sure what the undescores stand for. I am also confused (in this case and others) as to how the Me keyword works. If you could explain it in this case at least, It would get me on my way to understand other cases. For example, if you could replace Me with something else, what would it be? I understand that your code checks all controls to see if they are labels and if true checks if the tag number matches. It also searches if each control found has children etc... If all the labels and checkboxes where on a panel (say Panel1), what would you have done differently to simpify the code? This bit of code has made me understand quite a few things. Thanks! The underscores, e.g. _tag, are nothing more that a convention that I use
for local variable naming. The Me keyword provides a way to refer to the specific instance of a class or structure in which the code is currently executing. In this case Me refers to the instance of the form where the DynamicCheckBox_CheckChanged event handler is declared and it is used to pass a reference to the form to the FindControl function, which, by the way, could be declared in some other class or module outside the form. The first parameter of the FindControl function is declared as type Control which means that it will accept any variable that is a reference to an instance of a class that is derived Control. (Even a Form is derived from Control.) The FindControl function is recursive. This means that it continually calls itself until some condition or other is met. In this case the condition is that we have found the Label that we are looking for. Note that when it does call itself, it passes the control that it is currently dealing with as the first parameter, instead of Me. It is this taht allows it to 'walk' the 'tree' of controls on the form. If you knew that all the Labels thate you were interested in were on Panel1, then you would pass Panel1 as the first parameter instead of Me in the original call to FindFunction and only the controls that are 'children' of Panel1 (and their 'chidren') will be inspected. I didn't notice in your OP that you are using VB.NET 2005. In version 2.0 of the .NET Framework, (the version used by VB.NET 2005), some nice new methods were added to a number of classes. One in particular is the Control.ControlCollection.Find method. When you reference the Controls property of any control, you are actually dealing with a ControlCollection object and all it's properties and methods are automatically made available to you. The ControlCollection.Find method takes, as it's parameters, a string representing the name of a control and a boolean indicating whether or not all child controls should be searched and it returns an array of controls with 1 element for each control that matches the name parameter. If we use this method then the whole thing becomes much simpler: Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal e As EventArgs) Dim _tag As Object = CType(sender, Control).Tag If _tag IsNot Nothing Then Dim _c As Control() = Controls.Find("lblLabel" & CType(_tag, String), True) If _c.Length > 0 Then CType(_c(0), Label).Text = String.Empty End If End Sub and the the FindControl function is no longer required. Note that: Dim _c As Control() = Controls.Find("lblLabel" & CType(_tag, String), True) and Dim _c As Control() = Me.Controls.Find("lblLabel" & CType(_tag, String), True) are functionally equivalent and the call will search all the control on the form. Again, if you know that all the labels of interest are on Panel1 then the line could read: Dim _c As Control() = Panel1.Controls.Find("lblLabel" & CType(_tag, String), True) which will only search all the control on Panel1. One thing that you will learn as you go along is that there is often more then 1 way acheiving something. Some ways may be more efficient that others. it is a matter of finding what works for you. Show quoteHide quote "vbnewbie" <biol***@gmail.com> wrote in message news:1167521481.882494.3390@k21g2000cwa.googlegroups.com... > mediocrevbprogrammer.freed 's code WOULD work if the controls were > created at design time. > Since they are not, I get an error because the label have not been > declared (How could I declare them since they don't exist!) > What would be nice is to have some type of code that would let me > modify or get a value from a control property such as: > > tag as a variable (0, 1,2, etc) > lblLabel(tag).Text="" > > This is something very usfull in VBA > > The other part that does not work in mediocrevbprogrammer.freed 's is > the fact the number of labels that can be created in my app is > limitless. Which means I would need to be able to modify the number of > Cases, or get rid of the Case-End Case all together in favor of a > variable appended to the control name: lblLabel name = lblLabel(tag > number). > Is that at all possible? > > Stephany's code worked practically out of the box! Thanks! > > A few questions, though. > > I am not sure what the undescores stand for. > > I am also confused (in this case and others) as to how the Me keyword > works. If you could explain it in this case at least, It would get me > on my way to understand other cases. For example, if you could replace > Me with something else, what would it be? > > I understand that your code checks all controls to see if they are > labels and if true checks if the tag number matches. It also searches > if each control found has children etc... > If all the labels and checkboxes where on a panel (say Panel1), what > would you have done differently to simpify the code? > > This bit of code has made me understand quite a few things. Thanks! > Well, this time it did not work out of the box...
The problem is with the following line. If _c.Length > 0 Then CType(_c(0), Label).Text = String.Empty If I understand correctly, you declared c as Control Array of which the first and unique element would be the label we are looking for. However, when it checks for the c.Lengh, it comes up with 0. If I take that part out and keep: CType(_c(0), Label).Text = String.Empty I get an IndexOutOfRangeException It does find the label though, I checked that. It does not seem to populate the array... Show us the actual code (copy and paste) that you have inside the event
handler, especially the bit that shows how you determine that the label is actually found. The code I posted works for me. Show quoteHide quote "vbnewbie" <biol***@gmail.com> wrote in message news:1167532096.642585.67590@h40g2000cwb.googlegroups.com... > > Well, this time it did not work out of the box... > > > The problem is with the following line. > > If _c.Length > 0 Then CType(_c(0), Label).Text = String.Empty > > If I understand correctly, you declared c as Control Array of which the > first and unique element would be the label we are looking for. > > However, when it checks for the c.Lengh, it comes up with 0. > If I take that part out and keep: > CType(_c(0), Label).Text = String.Empty > I get an IndexOutOfRangeException > > It does find the label though, I checked that. > It does not seem to populate the array... > Sorry, my mistake...
I had forgoten to change the string part of label names in your code to match the one I actually use in my code (" lblLabel" as oposed to "lblFileLabel"). Tried it, it works. Thanks a million. Stephany... you've done it according to the requirements but I have a
suggestion. Avoid tagging the checkbox with an arbitrary numeric value and simply use the .Tag property to reference the label that is associated with it. Create the label first, tag it with a number (if these numbers are needed) then create the checkbox and assign the label reference as the tag. All done. Tom Show quoteHide quote "Stephany Young" <noone@localhost> wrote in message news:uPql$%23%23KHHA.4912@TK2MSFTNGP02.phx.gbl... > Your event handler will go something like this: > > Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal e > As EventArgs) > > Dim _tag As Object = CType(sender, Control).Tag > > If _tag IsNot Nothing Then > Dim _c As Control = FindControl(Me, GetType(Label), _tag) > If _c IsNot Nothing Then CType(_c, Label).Text = String.Empty > End If > > End Sub > > Private Function FindControl(ByVal start As Control, ByVal type as Type, > tag As Object) As Control > > For Each _c as Control In start.Controls > If _c.GetType() Is type Then > If _c.Tag IsNot Nothing AndAlso _c.Tag = tag Then Return _c > Else > If _c.HasChildren Then > Dim _cc As Control = FindControl(_c, type, tag) > If _cc IsNot Nothing Then Return _cc > End If > End If > Next > > Return Nothing > > End Function > > When you 'dynamically generate' your CheckBox controls, subscribe to the > event handler with something like: > > AddHandler chkCancel0.CheckChanged, AddressOf > DynamicCheckBox_CheckChanged > AddHandler chkCancel1.CheckChanged, AddressOf > DynamicCheckBox_CheckChanged > > etc. Note that the same handler is used. > > Note also that the event handler does not have a Handles clause. > > When any one of you dynamic CheckBoxes is clicked, the event handler is > called and sender is a reference to the CheckBox that was clicked. We then > attempt to get a reference to a Label control anywhere on the form that > has a matching Tag property. If we get one then we set it's Text Property > to an empty string. > > Let us konw how you get on. > > > "vbnewbie" <biol***@gmail.com> wrote in message > news:1167466759.111733.270610@n51g2000cwc.googlegroups.com... >>I am having problems accessing properties of dynamically generated >> objects in VB2005. Can someone please help? >> In a nutshell: >> My app creates an equal number of checkboxes and labels that share the >> same Tag number. (I thought it might help) >> The checkboxes name is a concatenation of "chkCancel" and a number that >> >> represents the order in which they were created: >> chkCancel0 (Tag = 0) >> chkCancel1 (Tag = 1) >> chkCancel2 (Tag = 2) >> etc... >> >> The same goes for the labels >> >> >> lblLabel0 (Tag = 0) >> lblLabel1 (Tag = 1) >> lblLabel2 (Tag = 2) >> etc... >> >> >> When the label is created, its text property is given a value >> (lblLabel.text = value). >> >> >> What I want to do, is clear that text property when I click on the >> corresponding checkbox. >> I want to do it with a common sub, handler, whatever, that will work >> for all checkboxes. >> My problem is how to acces the label text property of a dynamically >> created label. >> >> >> Pseudo code: >> >> >> lableTag = sender.tag >> if sender.checked=true then >> lblLabel(labelTag).text="" (this is the part I have trouble with) >> >> I don't seem to be able to reference any object created dynamically... >> >> >> It must be very simple for an experienced programmer, but not to >> vbnewbie... and it is driving me nuts! >> Thanks >> > > Tom,
> Stephany... you've done it according to the requirements but I have a I think that Stephany :-) can better use a sortedlist (or a hashtable but I > suggestion. prefer the sortedlist) http://msdn2.microsoft.com/en-us/library/ms132319.aspx Cor Show quoteHide quote "Tom Leylan" <tleylan@nospam.net> schreef in bericht news:OzPurZKLHHA.3552@TK2MSFTNGP03.phx.gbl... > Stephany... you've done it according to the requirements but I have a > suggestion. > > Avoid tagging the checkbox with an arbitrary numeric value and simply use > the .Tag property to reference the label that is associated with it. > Create the label first, tag it with a number (if these numbers are needed) > then create the checkbox and assign the label reference as the tag. All > done. > > Tom > > "Stephany Young" <noone@localhost> wrote in message > news:uPql$%23%23KHHA.4912@TK2MSFTNGP02.phx.gbl... >> Your event handler will go something like this: >> >> Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal e >> As EventArgs) >> >> Dim _tag As Object = CType(sender, Control).Tag >> >> If _tag IsNot Nothing Then >> Dim _c As Control = FindControl(Me, GetType(Label), _tag) >> If _c IsNot Nothing Then CType(_c, Label).Text = String.Empty >> End If >> >> End Sub >> >> Private Function FindControl(ByVal start As Control, ByVal type as Type, >> tag As Object) As Control >> >> For Each _c as Control In start.Controls >> If _c.GetType() Is type Then >> If _c.Tag IsNot Nothing AndAlso _c.Tag = tag Then Return _c >> Else >> If _c.HasChildren Then >> Dim _cc As Control = FindControl(_c, type, tag) >> If _cc IsNot Nothing Then Return _cc >> End If >> End If >> Next >> >> Return Nothing >> >> End Function >> >> When you 'dynamically generate' your CheckBox controls, subscribe to the >> event handler with something like: >> >> AddHandler chkCancel0.CheckChanged, AddressOf >> DynamicCheckBox_CheckChanged >> AddHandler chkCancel1.CheckChanged, AddressOf >> DynamicCheckBox_CheckChanged >> >> etc. Note that the same handler is used. >> >> Note also that the event handler does not have a Handles clause. >> >> When any one of you dynamic CheckBoxes is clicked, the event handler is >> called and sender is a reference to the CheckBox that was clicked. We >> then attempt to get a reference to a Label control anywhere on the form >> that has a matching Tag property. If we get one then we set it's Text >> Property to an empty string. >> >> Let us konw how you get on. >> >> >> "vbnewbie" <biol***@gmail.com> wrote in message >> news:1167466759.111733.270610@n51g2000cwc.googlegroups.com... >>>I am having problems accessing properties of dynamically generated >>> objects in VB2005. Can someone please help? >>> In a nutshell: >>> My app creates an equal number of checkboxes and labels that share the >>> same Tag number. (I thought it might help) >>> The checkboxes name is a concatenation of "chkCancel" and a number that >>> >>> represents the order in which they were created: >>> chkCancel0 (Tag = 0) >>> chkCancel1 (Tag = 1) >>> chkCancel2 (Tag = 2) >>> etc... >>> >>> The same goes for the labels >>> >>> >>> lblLabel0 (Tag = 0) >>> lblLabel1 (Tag = 1) >>> lblLabel2 (Tag = 2) >>> etc... >>> >>> >>> When the label is created, its text property is given a value >>> (lblLabel.text = value). >>> >>> >>> What I want to do, is clear that text property when I click on the >>> corresponding checkbox. >>> I want to do it with a common sub, handler, whatever, that will work >>> for all checkboxes. >>> My problem is how to acces the label text property of a dynamically >>> created label. >>> >>> >>> Pseudo code: >>> >>> >>> lableTag = sender.tag >>> if sender.checked=true then >>> lblLabel(labelTag).text="" (this is the part I have trouble with) >>> >>> I don't seem to be able to reference any object created dynamically... >>> >>> >>> It must be very simple for an experienced programmer, but not to >>> vbnewbie... and it is driving me nuts! >>> Thanks >>> >> >> > > Good call Tom!
I had been thinking that a better way to do it would have been to use a Dictionary(Of String, Label) where the key was the name of the relevant CheckBox control and the value was the Label control. But that way it still would have required a 'get' of the item of the dictionay before you could access the Label control. Your way, the code inside the event handler simply becomes: CType(CType(sender, Control).Tag, Label).Text = String.Empty assuming of course that the only controls that are subscribed to the event handler are the CheckBox controls of interest and that the Tag property for all of them contains a reference to the appropriate Label. Just goes to show how easy it is for any of us to get into a mind-set and to not think outside the square. Show quoteHide quote "Tom Leylan" <tleylan@nospam.net> wrote in message news:OzPurZKLHHA.3552@TK2MSFTNGP03.phx.gbl... > Stephany... you've done it according to the requirements but I have a > suggestion. > > Avoid tagging the checkbox with an arbitrary numeric value and simply use > the .Tag property to reference the label that is associated with it. > Create the label first, tag it with a number (if these numbers are needed) > then create the checkbox and assign the label reference as the tag. All > done. > > Tom > > "Stephany Young" <noone@localhost> wrote in message > news:uPql$%23%23KHHA.4912@TK2MSFTNGP02.phx.gbl... >> Your event handler will go something like this: >> >> Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal e >> As EventArgs) >> >> Dim _tag As Object = CType(sender, Control).Tag >> >> If _tag IsNot Nothing Then >> Dim _c As Control = FindControl(Me, GetType(Label), _tag) >> If _c IsNot Nothing Then CType(_c, Label).Text = String.Empty >> End If >> >> End Sub >> >> Private Function FindControl(ByVal start As Control, ByVal type as Type, >> tag As Object) As Control >> >> For Each _c as Control In start.Controls >> If _c.GetType() Is type Then >> If _c.Tag IsNot Nothing AndAlso _c.Tag = tag Then Return _c >> Else >> If _c.HasChildren Then >> Dim _cc As Control = FindControl(_c, type, tag) >> If _cc IsNot Nothing Then Return _cc >> End If >> End If >> Next >> >> Return Nothing >> >> End Function >> >> When you 'dynamically generate' your CheckBox controls, subscribe to the >> event handler with something like: >> >> AddHandler chkCancel0.CheckChanged, AddressOf >> DynamicCheckBox_CheckChanged >> AddHandler chkCancel1.CheckChanged, AddressOf >> DynamicCheckBox_CheckChanged >> >> etc. Note that the same handler is used. >> >> Note also that the event handler does not have a Handles clause. >> >> When any one of you dynamic CheckBoxes is clicked, the event handler is >> called and sender is a reference to the CheckBox that was clicked. We >> then attempt to get a reference to a Label control anywhere on the form >> that has a matching Tag property. If we get one then we set it's Text >> Property to an empty string. >> >> Let us konw how you get on. >> >> >> "vbnewbie" <biol***@gmail.com> wrote in message >> news:1167466759.111733.270610@n51g2000cwc.googlegroups.com... >>>I am having problems accessing properties of dynamically generated >>> objects in VB2005. Can someone please help? >>> In a nutshell: >>> My app creates an equal number of checkboxes and labels that share the >>> same Tag number. (I thought it might help) >>> The checkboxes name is a concatenation of "chkCancel" and a number that >>> >>> represents the order in which they were created: >>> chkCancel0 (Tag = 0) >>> chkCancel1 (Tag = 1) >>> chkCancel2 (Tag = 2) >>> etc... >>> >>> The same goes for the labels >>> >>> >>> lblLabel0 (Tag = 0) >>> lblLabel1 (Tag = 1) >>> lblLabel2 (Tag = 2) >>> etc... >>> >>> >>> When the label is created, its text property is given a value >>> (lblLabel.text = value). >>> >>> >>> What I want to do, is clear that text property when I click on the >>> corresponding checkbox. >>> I want to do it with a common sub, handler, whatever, that will work >>> for all checkboxes. >>> My problem is how to acces the label text property of a dynamically >>> created label. >>> >>> >>> Pseudo code: >>> >>> >>> lableTag = sender.tag >>> if sender.checked=true then >>> lblLabel(labelTag).text="" (this is the part I have trouble with) >>> >>> I don't seem to be able to reference any object created dynamically... >>> >>> >>> It must be very simple for an experienced programmer, but not to >>> vbnewbie... and it is driving me nuts! >>> Thanks >>> >> >> > > Personally I would (probably) go one step further. Considering they are
dynamic I wouldn't create a checkbox with a label but rather generate a hybrid control that contains a checkbox and a label. That frees up the tag property and permits me to leverage all the stuff available to a newly defined class. Additionally it means we don't walk the controls collection (which may include non-dynamic checkboxes) trying to recognize the checkboxes we want. We know we are looking for the hybrid objects. A simple (and separate) collection of the hybrids makes adding and deleting of the objects easy and insures we have access to each of them through the collection class. Rather than writing this in the application: CType(CType(sender, Control).Tag, Label).Text = String.Empty one should be able to write: Control.ClearLabel() Show quoteHide quote "Stephany Young" <noone@localhost> wrote in message news:%23n6dLwKLHHA.4928@TK2MSFTNGP06.phx.gbl... > Good call Tom! > > I had been thinking that a better way to do it would have been to use a > Dictionary(Of String, Label) where the key was the name of the relevant > CheckBox control and the value was the Label control. > > But that way it still would have required a 'get' of the item of the > dictionay before you could access the Label control. > > Your way, the code inside the event handler simply becomes: > > CType(CType(sender, Control).Tag, Label).Text = String.Empty > > assuming of course that the only controls that are subscribed to the event > handler are the CheckBox controls of interest and that the Tag property > for all of them contains a reference to the appropriate Label. > > Just goes to show how easy it is for any of us to get into a mind-set and > to not think outside the square. > > > "Tom Leylan" <tleylan@nospam.net> wrote in message > news:OzPurZKLHHA.3552@TK2MSFTNGP03.phx.gbl... >> Stephany... you've done it according to the requirements but I have a >> suggestion. >> >> Avoid tagging the checkbox with an arbitrary numeric value and simply use >> the .Tag property to reference the label that is associated with it. >> Create the label first, tag it with a number (if these numbers are >> needed) then create the checkbox and assign the label reference as the >> tag. All done. >> >> Tom >> >> "Stephany Young" <noone@localhost> wrote in message >> news:uPql$%23%23KHHA.4912@TK2MSFTNGP02.phx.gbl... >>> Your event handler will go something like this: >>> >>> Private Sub DynamicCheckBox_CheckChanged(ByVal sender As Object, ByVal >>> e As EventArgs) >>> >>> Dim _tag As Object = CType(sender, Control).Tag >>> >>> If _tag IsNot Nothing Then >>> Dim _c As Control = FindControl(Me, GetType(Label), _tag) >>> If _c IsNot Nothing Then CType(_c, Label).Text = String.Empty >>> End If >>> >>> End Sub >>> >>> Private Function FindControl(ByVal start As Control, ByVal type as >>> Type, tag As Object) As Control >>> >>> For Each _c as Control In start.Controls >>> If _c.GetType() Is type Then >>> If _c.Tag IsNot Nothing AndAlso _c.Tag = tag Then Return _c >>> Else >>> If _c.HasChildren Then >>> Dim _cc As Control = FindControl(_c, type, tag) >>> If _cc IsNot Nothing Then Return _cc >>> End If >>> End If >>> Next >>> >>> Return Nothing >>> >>> End Function >>> >>> When you 'dynamically generate' your CheckBox controls, subscribe to the >>> event handler with something like: >>> >>> AddHandler chkCancel0.CheckChanged, AddressOf >>> DynamicCheckBox_CheckChanged >>> AddHandler chkCancel1.CheckChanged, AddressOf >>> DynamicCheckBox_CheckChanged >>> >>> etc. Note that the same handler is used. >>> >>> Note also that the event handler does not have a Handles clause. >>> >>> When any one of you dynamic CheckBoxes is clicked, the event handler is >>> called and sender is a reference to the CheckBox that was clicked. We >>> then attempt to get a reference to a Label control anywhere on the form >>> that has a matching Tag property. If we get one then we set it's Text >>> Property to an empty string. >>> >>> Let us konw how you get on. >>> >>> >>> "vbnewbie" <biol***@gmail.com> wrote in message >>> news:1167466759.111733.270610@n51g2000cwc.googlegroups.com... >>>>I am having problems accessing properties of dynamically generated >>>> objects in VB2005. Can someone please help? >>>> In a nutshell: >>>> My app creates an equal number of checkboxes and labels that share the >>>> same Tag number. (I thought it might help) >>>> The checkboxes name is a concatenation of "chkCancel" and a number that >>>> >>>> represents the order in which they were created: >>>> chkCancel0 (Tag = 0) >>>> chkCancel1 (Tag = 1) >>>> chkCancel2 (Tag = 2) >>>> etc... >>>> >>>> The same goes for the labels >>>> >>>> >>>> lblLabel0 (Tag = 0) >>>> lblLabel1 (Tag = 1) >>>> lblLabel2 (Tag = 2) >>>> etc... >>>> >>>> >>>> When the label is created, its text property is given a value >>>> (lblLabel.text = value). >>>> >>>> >>>> What I want to do, is clear that text property when I click on the >>>> corresponding checkbox. >>>> I want to do it with a common sub, handler, whatever, that will work >>>> for all checkboxes. >>>> My problem is how to acces the label text property of a dynamically >>>> created label. >>>> >>>> >>>> Pseudo code: >>>> >>>> >>>> lableTag = sender.tag >>>> if sender.checked=true then >>>> lblLabel(labelTag).text="" (this is the part I have trouble with) >>>> >>>> I don't seem to be able to reference any object created dynamically... >>>> >>>> >>>> It must be very simple for an experienced programmer, but not to >>>> vbnewbie... and it is driving me nuts! >>>> Thanks >>>> >>> >>> >> >> > > My code is shorter than Stephany Young's:
Private Sub ChkCancel_CheckChanged(ByVal sender As Object, ByVal e As EventArgs) Handles chkCancel0.CheckChanged And chkCancel1.CheckChanged And chkCancel2.CheckChanged And chkCancel3.CheckChanged Select Case CType(sender, Control).Tag Case 0 lblLabel0.Text="" Case 1 lblLabel1.Text="" Case 2 lblLabel2.Text="" Case 3 lblLabel3.Text="" End Select End Sub Of course it will be longer depending on how many checkboxes you have. You could also add an error handler in case CType(sender, Control).Tag returned something it shouldn't. The error handler code would look like this: Case Else MessageBox.Show("Error!","Error!",MessageBoxButtons.OK,MessageBoxIcon.Hand,MessageBoxDefaultButton.Button1) This code would go betwwen the last line inside the Select and End Select mediocrevbprogrammer.freed Well Matthew ,
> My code is shorter than Stephany Young's: i am happy you swallowed bether :-)> It is a different aproach , with its own pro`s and con`s ( as with all aproaches :-) However i have one small mod you would better make label.Text="" to label.Text=string.empty as string.empty is a constant and doesn`t requir a scan through the string table ( it is faster , and safer "" vs " " oops ) regards Michel Show quoteHide quote "mediocrevbprogrammer.freed" <anonymous.160.matthew.sc***@gmail.com> schreef in bericht news:1167471113.630743.231300@a3g2000cwd.googlegroups.com... > My code is shorter than Stephany Young's: > > Private Sub ChkCancel_CheckChanged(ByVal sender As Object, ByVal e As > EventArgs) Handles chkCancel0.CheckChanged And chkCancel1.CheckChanged > And chkCancel2.CheckChanged And chkCancel3.CheckChanged > Select Case CType(sender, Control).Tag > Case 0 > lblLabel0.Text="" > Case 1 > lblLabel1.Text="" > Case 2 > lblLabel2.Text="" > Case 3 > lblLabel3.Text="" > End Select > End Sub > > Of course it will be longer depending on how many checkboxes you have. > You could also add an error handler in case CType(sender, Control).Tag > returned something it shouldn't. > The error handler code would look like this: > Case Else > > MessageBox.Show("Error!","Error!",MessageBoxButtons.OK,MessageBoxIcon.Hand,MessageBoxDefaultButton.Button1) > This code would go betwwen the last line inside the Select and End > Select > > mediocrevbprogrammer.freed > 
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