asked on

URGEN:Add a placeholder dynamically.

How do I dyanmiccaly add a placeholder to a table. I am adding a text box like this

For i = 0 To 25
Dim tr As TableRow = New TableRow

'make name cell with validator
Dim tc1 As TableCell = New TableCell

Dim txtName As TextBox = New TextBox
txtName.ID = "txtName" + i.ToString()

tc1.Controls.Add(txtName)
tr.Cells.Add(tc1)

Dim tcInet As TableCell = New TableCell
Dim txtDial As RadioButton = New RadioButton
Dim txtBroadband As RadioButton = New RadioButton

txtDial.ID = "txtINet" + i.ToString()
txtBroadband.ID = "txtINet" + i.ToString()

tcINet.Controls.Add(txtDial)
tcINet.Controls.Add(txtBroadband)

tr.Cells.Add(tcINet)

Table1.Rows.Add(tr)

I would like to add a placeholder after the INet control to later add text there.

ihenry

Try this

.....
.....
Dim ctl As New PlaceHolder()
ctl.Controls.Add( txtDial )
tcINet.Controls.Add(ctl)
.....
.....

Thogek

Is there a reason you cannot add a PlaceHolder control in exactly the same way you're currently adding the TextBox? You can then reference it by ID via the Page's FindControl method (http://msdn.microsoft.com/library/en-us/cpref/html/frlrfsystemwebuicontrolclassfindcontroltopic1.asp), in order to modify its contents, etc.

jui2ce

ASKER

I have tried adding it like this. However it does not find the control PlaceHolder3

Dim EtcLname As TableCell = New TableCell
Dim PLtxtname As PlaceHolder = New PlaceHolder

PLtxtname.ID = "PlaceHolder3"
EtcLname.Controls.Add(PLtxtname)
Etr.Cells.Add(EtcLname)

Table1.Rows.Add(Etr)

Thogek

What do you do to try to "find the control PlaceHolder3"?

Something like
Dim crtl As Control = Me.FindControl("PlaceHolder3")
Dim place As PlaceHolder = CType(ctrl, System.Web.UI.WebControls.PlaceHolder)
place.Controls.Add(new LiteralControl("Boo!"))
might work.

Or, if you're just looking to add text, you might wanna use a LiteralControl instead of a PlaceHolder, and just set the LiteralControl's Text property.

jui2ce

ASKER

That would work if I manually add the placeholder

<asp:PlaceHolder id="PlaceHolder3" runat="server"/>

That is the problem I need to add that dynamically.

ihenry

Please post more code might help us to identify your problem.

jui2ce

ASKER

<Script Runat="Server">
       Private Sub Page_Load()
            Dim i As Integer

            For i = 1 To 25
                        Dim tr As TableRow = New TableRow
                        Dim tc1 As TableCell = New TableCell
                        Dim Etcname As TableCell = New TableCell


                        Dim PLtxtname As PlaceHolder = New PlaceHolder
                        Dim txtName As TextBox = New TextBox


                        txtName.ID = "txtName" + i.ToString()
                        PLtxtname.ID = "PlaceHolder" + i.ToString()

                        tc1.Controls.Add(txtName)
                        Etcname.Controls.Add(PLtxtname)

                        tr.Cells.Add(tc1)
                        tr.Cells.Add(Etcname)

                        Table1.Rows.Add(tr)
            Next
            End Sub

      Sub Button_Click( s As Object, e As EventArgs )
       Dim i As Integer

                        For i = 1 To 25
                              dim txtName As TextBox
                              Dim PLtxtname As PlaceHolder

                              Dim ctxtName
                              dim ePlaceHolder

                              ctxtName="txtName" + i.ToString()
                              ePlaceHolder="PlaceHolder" + i.ToString()

            txtName = CType(Me.Page.FindControl(ctxtName),TextBox)
            PLtxtname = CType(Me.Page.FindControl(ePlaceHolder),PlaceHolder)

            if not txtName is Nothing then

              ePlaceHolder.Controls.Add(new LiteralControl("test"))

                              end if
                        Next
                  End Sub


</Script>

<form Runat="Server">

<asp:Table id="Table1"
                   BackImageUrl="url"
                   Border="0"
                   CellSpacing="1"
                   CellPadding="1"
                   GridLines="Both"
                   HorizontalAlign="Center"
                   runat="server">


                  </asp:Table>
                        <asp:Button Text="Add" OnClick="Button_Click" Runat="Server" />
</form>

ihenry

I copied and pasted your code to my vs.net and got this exception,

=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Public member 'Controls' on type 'String' not found.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.MissingMemberException: Public member 'Controls' on type 'String' not found.

Source Error:

Line 68: If Not txtName Is Nothing Then
Line 69:
Line 70: ePlaceHolder.Controls.Add(New LiteralControl("test"))
Line 71:
Line 72: End If
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

And I modified the Button_Click event
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Dim i As Integer

For i = 1 To 25
Dim txtName As TextBox
Dim PLtxtname As PlaceHolder

Dim ctxtName As String
Dim ePlaceHolder As String

ctxtName = "txtName" + i.ToString()
ePlaceHolder = "PlaceHolder" + i.ToString()

txtName = CType(Me.Page.FindControl(ctxtName), TextBox)
PLtxtname = CType(Me.Page.FindControl(ePlaceHolder), PlaceHolder)

If Not txtName Is Nothing Then

PLtxtname.Controls.Add(New LiteralControl("test"))

End If
Next
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-

Now it seems the code is working without any problem. Can you try that?

Thogek

> That would work if I manually add the placeholder
> That is the problem I need to add that dynamically.

It should work either way.

However, you're code example above appears to be using ePlaceHolder (a string) and PLtxtname (a PlaceHolder) interchangably, which won't work -- my example code adds the LiteralControl to a PlaceHolder's Controls collection, not to a string's, which has no such collection -- and explains the error ihenry is seeing. ihenry's code example seems to fix that immediate problem.

ASKER CERTIFIED SOLUTION

jnhorst

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