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Need button to programmatically add controls to a page

So I have a button on my page which I'd like to add a few textboxes and a fileupload control when clicked. It only works the first time the user clicks the button. Here's the code. Note: "pnlContainer" refers to an asp panel that's already on the page in markup.

       protected void addFileUploader(object sender, System.EventArgs e)
        {
            int cnt = Convert.ToInt32(Session["cnt"]);
            String codeBox = "txtCode" + cnt;
            String versionBox = "txtVersion" + cnt;
            String keywordBox = "txtKeyword" + cnt;
            String uploader = "fUp" + cnt;
            TextBox txtCode = new TextBox();
            txtCode.ID = codeBox;
            txtCode.Width = Unit.Pixel(70);
            pnlContainer.Controls.Add(txtCode);
            pnlContainer.Controls.Add(new LiteralControl("&nbsp;"));
            TextBox txtVersion = new TextBox();
            txtVersion.ID = versionBox;
            txtVersion.Width = Unit.Pixel(70);
            pnlContainer.Controls.Add(txtVersion);
            pnlContainer.Controls.Add(new LiteralControl("&nbsp;"));
            TextBox txtKeyword = new TextBox();
            txtKeyword.Width = Unit.Pixel(70);
            txtKeyword.ID = keywordBox;
            pnlContainer.Controls.Add(txtKeyword);
            pnlContainer.Controls.Add(new LiteralControl("<br/>"));
            FileUpload fup = new FileUpload();
            fUp.ID = uploader;
            pnlContainer.Controls.Add(fup);
            pnlContainer.Controls.Add(new LiteralControl("<br/>"));
            cnt++;
            pnlContainer.DataBind();
        }

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HainKurt

could not get the logic here... you have only one pnlContainer on your page I guess and each time you are adding to this panel? are you clearing the controls each time? if you dont clear, you should get multiple controls on panel... also I dont see how this sub is called from button click... are you using some repeater? how many "add" button do you have on your page? do you have a link to share? also can you please post the aspx code and also button_click code...

Ironhoofs

I think you forgot to update the session variable.

line 27: cnt++;

should probably read something like:

Session["cnt"] = Convert.ToString(cnt++);

ASKER CERTIFIED SOLUTION

Swapnil

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asphaltninja

ASKER

hello netswap and thanks for your help. How would I also be able to have new texboxes appear when the button is clicked?

Swapnil

Hi asphaltninja,

You can add additional textbox in same way, file upload control is added in javascript.

Below is the code snippet you can use.

var newUploadBox = document.createElement("input");
uploadArea.appendChild(newUploadBox);
newUploadBox.setAttribute("id", "txt" + addFileUploadBox.lastAssignedId);
newUploadBox.setAttribute("name", "txt:" + addFileUploadBox.lastAssignedId);

Thanks,
netswap.

asphaltninja

ASKER

HainKurt

"could not get the logic here... you have only one pnlContainer on your page I guess and each time you are adding to this panel? are you clearing the controls each time? if you dont clear, you should get multiple controls on panel... also I dont see how this sub is called from button click... are you using some repeater? how many "add" button do you have on your page? do you have a link to share? also can you please post the aspx code and also button_click code..."

The "addFileUploader" is handling the button click event. Yes I have only one asp:panel named "pnlContainer" on the page. I'm not clearing the controls each time Here's the markup:

<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Individual.aspx.cs" MasterPageFile="~/core.Master" Inherits="fileSystemLoader.Individual" %>

<asp:Content ContentPlaceHolderID="headContent" runat="server">Individual Upload Page</asp:Content>

<asp:Content ContentPlaceHolderID="mainContent" runat="server">
<div>
<span style="color:red;">Press the "Add" button to include more files.</span>
</div>
<asp:Panel ID="pnlContainer" runat="server">
<asp:TextBox ID="txtCode" runat="server" HoveredStyle-BackColor="Yellow" Width="70px"/>&nbsp;<asp:TextBox runat="server" HoveredStyle-BackColor="Yellow" ID="txtVersion" Width="70px"/>
&nbsp;<asp:TextBox ID="txtKeyword" runat="server" HoveredStyle-BackColor="Yellow" Width="70px"/><br />
<asp:FileUpload ID="fUp" runat="server" Font-Names="Verdana"/><br />
</asp:Panel>
<asp:Button ID="btnAdd" Text="Add" runat="server" OnClick="addFileUploader"/>
<asp:Button ID="btnSubmit" runat="server" OnClick="btnSubmit_Click" Text="Upload" Font-Names="Verdana"/>
</asp:Content>

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HainKurt

did you do this

Session["cnt"] = Convert.ToString(cnt++);

(suggested by Ironhoofs) also

are you setting Session["cnt"] = "1" on page_load?

asphaltninja

ASKER

yes, I added the Session["cnt"] = Convert.ToString(cnt++);
and I set the session variable in page_load as so:
if(!this.isPostBack){
Session["cnt"] = 1;

}
should it not be inside the postback loop?

asphaltninja

ASKER

Okay netswap, your method appears to be working. I can retrieve the values for the files, but how to i retrieve the values from the texboxes?

SOLUTION

Swapnil

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asphaltninja

ASKER

hi netswap,

the values in the text inputs are additional values that will eventually go into a database with the file, like keyword tags.

Kumaraswamy R

This question has been classified as abandoned and is being closed as part of the Cleanup Program. See my comment at the end of the question for more details.