I'm dynamically creating/populating a checkbox list and adding it to a web
form.
I want to when checking an item in the list have the autopostback retrieve
the
selected item.

I'm dynamically adding that control as:
Protected WithEvents userSelectionList, Ulist2 As
System.Web.UI.WebControls.CheckBoxList
Protected WithEvents checkboxcontainer As PlaceHolder

For i = 0
Dim selectedItem As New ListItem(appstring, appstring)
'selectedItem.Selected = True
userselectionlist.Items.Add(selectedItem)
Next i

checkboxcontainer.Controls.Add(userselectionlist)

etc..
td1.Controls.Add(checkboxcontainer)
tr1.Controls.Add(td1)
table1.Controls.Add(tr1)
form1.Controls.Add(table1)

My asp looks something like this:

<form id="Form1" method="post" runat="server">
<asp:Table Runat="server" ID="Table1">
<asp:TableRow ID='appinfo' Visible=false Width='250'>
<asp:TableCell ID='appname' Visible=true ColumnSpan="1"
HorizontalAlign="Right">
<br>
<asp:Literal id="mySelections" Runat="server"></asp:Literal>
<asp:PlaceHolder ID="checkboxcontainer" Runat="server" />
<asp:CheckBoxList ID="mylist" Runat="server" />
<br>
</asp:TableCell>
</asp:TableRow>

And retrieving the list on the postback which I'm calling in page_init:

Sub apppb()
Dim i, x As Integer

'Dim userSelectionList As New CheckBoxList
userSelectionList = CType(form1.FindControl("mylist"), CheckBoxList)
Ulist2 = CType(form1.FindControl("mylist"), CheckBoxList)
Try
For x = 0 To Ulist2.Items.Count - 1
If Ulist2.Items(x).Selected = True Then
results.Text += Ulist2.Items(x).Value
'mySelections.Text += userSelectionList.Items(x).Value

End If
Next x
Catch ex As Exception

End Try
End Sub

Yet no value for the selected item.

Please help. I've used dynamic controls before and I think
maybe there may be a problem when I redeclare the control
for viewstate on the postback i.e.:

There are some complications in finding the checkboxlist control maybe because
it's binded to a placeholder - checkboxcontainer.

My page init looks something like:

InitializeComponent()
If Not IsPostBack Then
buildform(sender, e)
Else

'userSelectionList = New CheckBoxList
'checkboxcontainer = New PlaceHolder
'userSelectionList = CType(form1.FindControl("mylist"),
CheckBoxList)
'checkboxcontainer.Controls.Add(userSelectionList)
'checkcontainer()
buildform(sender, e)
apppb()

End If

Can someone get this scenario to work?

Regards;

tjt:

segue,

In the CBL's properties, set AutoPostBack = true

As well, you will want to set up a server side event that is called
whenever a user clicks the checkbox (the click event). THis way you can
get the sender, and the EventArgs from the postback and figure out what
Item called the post back.

/RT
segue wrote:
> I'm dynamically creating/populating a checkbox list and adding it to a web
> form.
> I want to when checking an item in the list have the autopostback retrieve
> the
> selected item.
>
> I'm dynamically adding that control as:
> Protected WithEvents userSelectionList, Ulist2 As
> System.Web.UI.WebControls.CheckBoxList
> Protected WithEvents checkboxcontainer As PlaceHolder
>
> For i = 0
> Dim selectedItem As New ListItem(appstring, appstring)
> 'selectedItem.Selected = True
> userselectionlist.Items.Add(selectedItem)
> Next i
>
> checkboxcontainer.Controls.Add(userselectionlist)
>
> etc..
> td1.Controls.Add(checkboxcontainer)
> tr1.Controls.Add(td1)
> table1.Controls.Add(tr1)
> form1.Controls.Add(table1)
>
> My asp looks something like this:
>
> <form id="Form1" method="post" runat="server">
> <asp:Table Runat="server" ID="Table1">
> <asp:TableRow ID='appinfo' Visible=false Width='250'>
> <asp:TableCell ID='appname' Visible=true ColumnSpan="1"
> HorizontalAlign="Right">
> <br>
> <asp:Literal id="mySelections" Runat="server"></asp:Literal>
> <asp:PlaceHolder ID="checkboxcontainer" Runat="server" />
> <asp:CheckBoxList ID="mylist" Runat="server" />
> <br>
> </asp:TableCell>
> </asp:TableRow>
>
> And retrieving the list on the postback which I'm calling in page_init:
>
> Sub apppb()
> Dim i, x As Integer
>
> 'Dim userSelectionList As New CheckBoxList
> userSelectionList = CType(form1.FindControl("mylist"), CheckBoxList)
> Ulist2 = CType(form1.FindControl("mylist"), CheckBoxList)
> Try
> For x = 0 To Ulist2.Items.Count - 1
> If Ulist2.Items(x).Selected = True Then
> results.Text += Ulist2.Items(x).Value
> 'mySelections.Text += userSelectionList.Items(x).Value
>
> End If
> Next x
> Catch ex As Exception
>
> End Try
> End Sub
>
> Yet no value for the selected item.
>
> Please help. I've used dynamic controls before and I think
> maybe there may be a problem when I redeclare the control
> for viewstate on the postback i.e.:
>
> There are some complications in finding the checkboxlist control maybe because
> it's binded to a placeholder - checkboxcontainer.
>
> My page init looks something like:
>
> InitializeComponent()
> If Not IsPostBack Then
> buildform(sender, e)
> Else
>
> 'userSelectionList = New CheckBoxList
> 'checkboxcontainer = New PlaceHolder
> 'userSelectionList = CType(form1.FindControl("mylist"),
> CheckBoxList)
> 'checkboxcontainer.Controls.Add(userSelectionList)
> 'checkcontainer()
> buildform(sender, e)
> apppb()
>
> End If
>
> Can someone get this scenario to work?
>
> Regards;
>
> tjt:
>
>

Hi;

I found that you need to repopulate the control before you loop
through it on a postback to see what was selected.

Regards;

Segue

"Ryan Ternier" wrote:

> segue,
>
> In the CBL's properties, set AutoPostBack = true
>
> As well, you will want to set up a server side event that is called
> whenever a user clicks the checkbox (the click event). THis way you can
> get the sender, and the EventArgs from the postback and figure out what
> Item called the post back.
>
> /RT
> segue wrote:
> > I'm dynamically creating/populating a checkbox list and adding it to a web
> > form.
> > I want to when checking an item in the list have the autopostback retrieve
> > the
> > selected item.
> >
> > I'm dynamically adding that control as:
> > Protected WithEvents userSelectionList, Ulist2 As
> > System.Web.UI.WebControls.CheckBoxList
> > Protected WithEvents checkboxcontainer As PlaceHolder
> >
> > For i = 0
> > Dim selectedItem As New ListItem(appstring, appstring)
> > 'selectedItem.Selected = True
> > userselectionlist.Items.Add(selectedItem)
> > Next i
> >
> > checkboxcontainer.Controls.Add(userselectionlist)
> >
> > etc..
> > td1.Controls.Add(checkboxcontainer)
> > tr1.Controls.Add(td1)
> > table1.Controls.Add(tr1)
> > form1.Controls.Add(table1)
> >
> > My asp looks something like this:
> >
> > <form id="Form1" method="post" runat="server">
> > <asp:Table Runat="server" ID="Table1">
> > <asp:TableRow ID='appinfo' Visible=false Width='250'>
> > <asp:TableCell ID='appname' Visible=true ColumnSpan="1"
> > HorizontalAlign="Right">
> > <br>
> > <asp:Literal id="mySelections" Runat="server"></asp:Literal>
> > <asp:PlaceHolder ID="checkboxcontainer" Runat="server" />
> > <asp:CheckBoxList ID="mylist" Runat="server" />
> > <br>
> > </asp:TableCell>
> > </asp:TableRow>
> >
> > And retrieving the list on the postback which I'm calling in page_init:
> >
> > Sub apppb()
> > Dim i, x As Integer
> >
> > 'Dim userSelectionList As New CheckBoxList
> > userSelectionList = CType(form1.FindControl("mylist"), CheckBoxList)
> > Ulist2 = CType(form1.FindControl("mylist"), CheckBoxList)
> > Try
> > For x = 0 To Ulist2.Items.Count - 1
> > If Ulist2.Items(x).Selected = True Then
> > results.Text += Ulist2.Items(x).Value
> > 'mySelections.Text += userSelectionList.Items(x).Value
> >
> > End If
> > Next x
> > Catch ex As Exception
> >
> > End Try
> > End Sub
> >
> > Yet no value for the selected item.
> >
> > Please help. I've used dynamic controls before and I think
> > maybe there may be a problem when I redeclare the control
> > for viewstate on the postback i.e.:
> >
> > There are some complications in finding the checkboxlist control maybe because
> > it's binded to a placeholder - checkboxcontainer.
> >
> > My page init looks something like:
> >
> > InitializeComponent()
> > If Not IsPostBack Then
> > buildform(sender, e)
> > Else
> >
> > 'userSelectionList = New CheckBoxList
> > 'checkboxcontainer = New PlaceHolder
> > 'userSelectionList = CType(form1.FindControl("mylist"),
> > CheckBoxList)
> > 'checkboxcontainer.Controls.Add(userSelectionList)
> > 'checkcontainer()
> > buildform(sender, e)
> > apppb()
> >
> > End If
> >
> > Can someone get this scenario to work?
> >
> > Regards;
> >
> > tjt:
> >
> >
>