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Dynamic Web Textboxes

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Topic

jhermiz

3564 Posts

Posted - 2006-12-14 : 11:11:23

I can do this:

For i As Integer = 1 To n
Panel1.Controls.Add(New TextBox())
Next

To dynamically create n textboxes onto a panel.
I can also do this to create one:

Dim t as New Textbox()
Panel1.Controls.Add(t)

But the issue is if I put the above code behind a button and click it say n times it still only creates one button. I need to be able to display to the user a button, when he / she clicks it it creates a dynamic textbox, they fill it out, and have the option to click that same button again. If they click it again it should create another text box.

I cant use the loop cause i dont want to ask the user how many textboxes...so I just want them to have the ability to click it once / twice / three / n times...

Anyone have an idea ?

Thanks

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jhermiz

3564 Posts

Posted - 2006-12-14 : 11:12:46

Just to add on even if I change the id still no luck:

Protected Sub AddTextBox(ByVal i As Integer)
Dim t As New TextBox

t.ID = "T" & CType(i, String)

form1.Controls.Add(t)
End Sub

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jsmith8858
Dr. Cross Join

7423 Posts

Posted - 2006-12-14 : 11:51:03

might be a viewstate issue? Does Panel1 have its ViewState enabled?

- Jeff

jhermiz

3564 Posts

Posted - 2006-12-14 : 12:21:50

quote:
Originally posted by jsmith8858

might be a viewstate issue? Does Panel1 have its ViewState enabled?

- Jeff

Hi jeff yes viewstate is enabled in Panel1.

I tried something to this effect allowing the user to enter the number, i think that will work:


 Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Select Case Me.Button1.Text
            Case "Add Sites"
                For i As Integer = 0 To Me.TextBox1.Text - 1
                    Me.Panel1.Controls.Add(New LiteralControl("<br>Enter site " & (i + 1).ToString() & ": "))
                    Me.Panel1.Controls.Add(New TextBox())
                Next
                Me.Button1.Text = "Generate Page"
                Me.Button1.ForeColor = Drawing.Color.Green

            Case "Generate Page"
                Dim AList As New ArrayList
                For Each c As Control In Panel1.Controls
                    If c.GetType().ToString().Equals("System.Web.UI.WebControls.TextBox") And c.ID <> "TextBox1" Then
                        AList.Add(CType(c, TextBox).Text)
                        'Response.Write((CType(c, TextBox).Text))
                    End If
                Next
        End Select

    End Sub

However the IF c.GetType().ToString().Equals...
Never adds any of the text from the dynamically controlled text boxes to the arraylist. Its almost like it doesnt know they exist.
Even the control count doesnt list enough items...As I am creating literal controls right after it. Any reason why that IF doesnt execute.

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jsmith8858
Dr. Cross Join

7423 Posts

Posted - 2006-12-14 : 12:35:50

hmmm .. still not sure.

About checking types: you can do this, I think it's easier and perhaps more efficient (no string conversions and comparisons):

if TypeOf(c) Is TextBox Then
....
End if

I would think that you'd want to store a collection or array or list of some sort with the items that the user is building, store that list in the viewstate, and then bind a repeater, dataGrid or DataList to that array/collection and output your textbox's there .... this way, they should survive postbacks, and you can store information regarding the collection of items that the user is creating. Even just an array of ints, from 1..N, that you bind to might do the trick...

- Jeff

jhermiz

3564 Posts

Posted - 2006-12-14 : 13:06:38

Yep Ill deal with the repeater later as of right now Im just trying to get some sort of concept of getting this to work. I had tried TypeOf(object) already with the same effects. It doesnt seem to recognize my dynamic text boxes, maybe generating them behind a click button is not the way to go...however I would need that event behind the button to do this sort of thing though :(.

I guess Im stumped for now I will keep playing with it.


   Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Select Case Me.Button1.Text
            Case "Add Sites"
                For i As Integer = 0 To Me.TextBox1.Text - 1
                    Me.Panel1.Controls.Add(New LiteralControl("<br>Enter site " & (i + 1).ToString() & ": "))
                    Me.Panel1.Controls.Add(New TextBox())
                Next
                Me.Button1.Text = "Generate Page"
                Me.Button1.ForeColor = Drawing.Color.Green
            Case "Generate Page"
                Dim AList As New ArrayList
                For Each c As Control In Panel1.Controls
                    If TypeOf (c) Is TextBox Then
                        AList.Add(CType(c, TextBox).Text)
                    End If
                Next
        End Select
    End Sub

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jhermiz

3564 Posts

Posted - 2006-12-14 : 13:29:38

O o found this on the MS site:

quote:

Note When you create dynamic controls on a Web Form, you must create the controls and add them to the controls collection in either the Page_Init event handler or the Page_Load event handler. Otherwise, the controls may not behave as expected.

Err...but I need them created dynamically behind a click of the button...:(

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jhermiz

3564 Posts

Posted - 2006-12-14 : 13:57:01

quote:
Originally posted by jhermiz

O o found this on the MS site:

quote:

Note When you create dynamic controls on a Web Form, you must create the controls and add them to the controls collection in either the Page_Init event handler or the Page_Load event handler. Otherwise, the controls may not behave as expected.

Err...but I need them created dynamically behind a click of the button...:(

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

Jeff after they are created on the first post back they are completly lost. I tried a test by creating one button that creates the dynamic text boxes and another button that does absolutely nothing but clicking on that second button makes the text boxes go bye bye :|.

Issue is I need someone to fill them out and then run an event after they fill them out...

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

DustinMichaels
Constraint Violating Yak Guru

464 Posts

Posted - 2006-12-14 : 13:57:03

quote:

O o found this on the MS site:

quote:
--------------------------------------------------------------------------------

Note When you create dynamic controls on a Web Form, you must create the controls and add them to the controls collection in either the Page_Init event handler or the Page_Load event handler. Otherwise, the controls may not behave as expected.

--------------------------------------------------------------------------------

Err...but I need them created dynamically behind a click of the button...:(

The page init / page load event gets fired on every request. If you want to check to see if the button was clicked use code like this.


Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
    If Not (Request.Form(YourButton.UniqueID) Is Nothing) Then
       CreateTextBoxes()
    End If
End Sub

jhermiz

3564 Posts

Posted - 2006-12-14 : 13:58:41

quote:
Originally posted by DustinMichaels

quote:

O o found this on the MS site:

quote:
--------------------------------------------------------------------------------

Note When you create dynamic controls on a Web Form, you must create the controls and add them to the controls collection in either the Page_Init event handler or the Page_Load event handler. Otherwise, the controls may not behave as expected.

--------------------------------------------------------------------------------

Err...but I need them created dynamically behind a click of the button...:(

The page init / page load event gets fired on every request. If you want to check to see if the button was clicked use code like this.

Protected Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
Dim button As New System.Web.UI.WebControls.Button()

If Not (Request.Form(YourButton.UniqueID) Is Nothing) Then
CreateTextBoxes()
End If

End Sub

Well I can get them created the issue is once there is another post back they are gone (they being the dynamic text boxes).
I had code run to create them, after they are created I clicked a button that simply does nothing, but since it autopostsback the dynamic boxes disappeared...

So I think that is the issue, how to handle this is another question :).

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

jsmith8858
Dr. Cross Join

7423 Posts

Posted - 2006-12-14 : 14:22:04

hi Jon -- here is some sample code to help you out, using the technique that I described. We create a class of something called "textboxItem" that will represent whatever info each textbox is holding, and we maintain and store this in an ArrayList in the viewstate. Then, we simply bind a repeater to the ArrayList to display the text boxes.

On a postback, however, we need to get the values out of the textboxes that have been created and store them into the ArrayList, which you see I do on the bAdd_Click() event. Might be better to do this on all postbacks.

anyway, hope this is somewhat helpful.

web page:


<%@ Page Language="vb" AutoEventWireup="false" Codebehind="Example.aspx.vb" Inherits="Test.Example"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
<HTML>
	<HEAD>
		<title>Example</title>
		<meta content="http://schemas.microsoft.com/intellisense/ie5" name="vs_targetSchema">
	</HEAD>
	<body>
		<form id="Form1" method="post" runat="server">
			<asp:button id="bAdd" Text="Click here" Runat="server"></asp:button><br>
			<br>
			<asp:repeater id="rpt1" Runat="server">
				<ItemTemplate>
					Text box #<%# Container.DataItem.Index%>:
					<asp:TextBox Runat="server" ID="txtBox" Text="<%# Container.DataItem.Value%>" /><br>
				</ItemTemplate>
			</asp:repeater></form>
	</body>
</HTML>

and the code behind:


Public Class Example
    Inherits System.Web.UI.Page

    Protected WithEvents bAdd As System.Web.UI.WebControls.Button
    Protected WithEvents pnl1 As System.Web.UI.WebControls.Panel
    Protected WithEvents rpt1 As System.Web.UI.WebControls.Repeater

    <Serializable()> Public Class TextBoxItem
        Public Index As Integer
        Public Value As String

        Public Sub New(ByVal pIndex As Integer, ByVal pValue As String)
            Index = pIndex
            Value = pValue
        End Sub
    End Class

    Public Property Items() As ArrayList
        Get
            Return CType(Viewstate("Items"), ArrayList)
        End Get
        Set(ByVal Value As ArrayList)
            viewstate("Items") = Value
        End Set
    End Property

    Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'Put user code to initialize the page here
        If Not IsPostBack Then
            InitTextBoxes()
            LoadItems()
        End If
    End Sub

    Private Sub InitTextBoxes()
        Items = New ArrayList
    End Sub

    Private Sub LoadItems()
        rpt1.DataSource = Items
        rpt1.DataBind()
    End Sub

    Private Sub bAdd_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles bAdd.Click
        ' first, save values of all existing items:
        Dim item As RepeaterItem

        For i As Integer = 0 To rpt1.Items.Count - 1
            item = rpt1.Items(i)
            Dim txt As TextBox = CType(item.FindControl("txtBox"), TextBox)
            If Not txt Is Nothing Then
                CType(Items.Item(i), TextBoxItem).Value = txt.Text
            End If
        Next

        ' now add a new one:
        Items.Add(New TextBoxItem(Items.Count, ""))

        LoadItems()
    End Sub
End Class

- Jeff

jhermiz

3564 Posts

Posted - 2006-12-14 : 14:52:33

Hey jeff sorry I didnt get back to you, the problems I had suddenly went away.

This is SEVERLY BAD BAD CODE that I am going to post, but it was just something that I had to try.
It ended up looking pretty cool, so the code is only for testing purposes, please do not use it in production as it is very dirty especially the CreatePage button.

In any event anyone who wants to try it create a project and use the following html:


<%@ Page Language="VB" AutoEventWireup="false" CodeFile="Default.aspx.vb" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml" >
<head id="Head1" runat="server">
    <title>Untitled Page</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
         <asp:Panel ID="Panel1" runat="server" Height="50px" Width="1000px">
            How many sites:
            <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox> 
            <asp:Button ID="Button1" runat="server" Text="Button" />
            <asp:Button ID="Button2" runat="server" Text="Cancel" />
            <asp:RangeValidator ID="RangeValidator1" runat="server" ControlToValidate="TextBox1"
                ErrorMessage="No way!" MaximumValue="100" MinimumValue="1" Type="Integer"></asp:RangeValidator> 
        </asp:Panel>
         
    </div>
    </form>
</body>
</html>

And the following code behind:



Partial Class _Default
    Inherits System.Web.UI.Page
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button1.Click
        Select Case Me.Button1.Text
            Case "Add Site(s)"
                Session("PageCount") = Me.TextBox1.Text
                Me.Button1.Text = "Generate Page"
                Me.Button1.ForeColor = Drawing.Color.Green
            Case "Generate Page"
                Dim AList As New ArrayList
                For Each c As Control In Panel1.Controls
                    If TypeOf (c) Is TextBox And c.ID Is Nothing Then
                        AList.Add(CType(c, TextBox).Text)
                    End If
                Next
                CreatePage(AList)
        End Select
    End Sub
    Protected Sub CreatePage(ByVal a As ArrayList)
        Dim iR As Integer
        Dim k As Integer
        Dim count As Integer
        k = 0
        If Session("PageCount") Mod 2 = 0 Then
            'its even
            iR = CType(Session("PageCount"), Integer) / 2
        Else
            iR = (CType(Session("PageCount"), Integer) / 2) + 1
        End If
        Response.Write("<table width='100%' height='100%' cellpadding='0' cellspacing='0'>")
        count = 0

        For i As Integer = 0 To iR - 1
            Response.Write("<tr>")
            While count < a.Count
                Response.Write("<td>")
                Response.Write("<iframe src='" & a(k).ToString & "' width='100%' height='100%'></iframe></td>")
                count = count + 1
                k += 1
                If count Mod 2 = 0 Then
                    Exit While
                End If
            End While
            Response.Write("</tr>")
        Next
        Response.Write("</table>")
    End Sub
    Protected Sub IterateThroughControls()
        For Each c As Control In Panel1.Controls
            If TypeOf (c) Is TextBox And c.ID Is Nothing Then
                CType(c, TextBox).Text = "http://"
            End If
        Next
    End Sub
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        If Me.TextBox1.Text.Length > 0 Then
            For i As Integer = 0 To Me.TextBox1.Text - 1
                Me.Panel1.Controls.Add(New LiteralControl("<br>Enter site " & (i + 1).ToString() & ": "))
                Me.Panel1.Controls.Add(New TextBox())
            Next
            IterateThroughControls()
        End If

        If Not IsPostBack Then
            Me.Button1.Text = "Add Site(s)"
            Me.Button1.ForeColor = Drawing.Color.Red
        End If
    End Sub
    Protected Sub Button2_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles Button2.Click
        For Each c As Control In Panel1.Controls
            If TypeOf (c) Is TextBox And c.ID Is Nothing Then
                CType(c, TextBox).Dispose()
            End If
        Next

        Me.Button1.Text = "Add Site(s)"
        Me.Button1.ForeColor = Drawing.Color.Red
        Me.TextBox1.Text = 0
    End Sub
End Class

I am certain jeff's code is cleaner and more accurate but this was just something I had to play with. Nifty IFRAMES :).

Keeping the web experience alive -- [url]http://www.web-impulse.com[/url]

RS Blog -- [url]http://weblogs.sqlteam.com/jhermiz[/url]

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