Wanted to create a dynamic table with 4 columns in a row

Phani Kumar

In a master page

I am trying to create a dynamic table with 4 columns for a table row.

Actual my requirement is I have text box in which I will give a number basing on that number input it should create 4 column's in a row

ex: in my text box i/p is 5 then table should created in the below format

Label1	TetBox1	Label2	TextBox2
Label3	TextBox3	Label4	TextBox4
Label5	TextBox5

in this first column Level1 and textbox1 in 2nd column in the same way third column and fourth column's level2 and textbox2

in the above mentioned format my dynamic table should be created.

I have tried but recieving an error. Help is needed ASAP, As I stuck with this functionality

15 Replies

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ali tuncer10y ago
Now you are creating a table with id "tabletxtRoundNumber" in server side, with this line:
table = new Table();
table.ID = "table" + chosenDropDown.ID;
Page.Form.Controls.Add(table);

Initially, you were trying to find a table with id "tabletxtRoundNumber" this way, but it didn't exist..
Table table = // new Table();
(Table)Page.Form.FindControl("table" + chosenDropDown.ID);

Anyway, I am glad it is working now..
Phani Kumar10y ago
Yes the functionality is working

I have placed a panel but I am not adding this table to that panel
now I added it, it is displaying fine.
Thanks for your help.

Here is my part of code

protected void txtRoundNumber_TextChanged(object sender, EventArgs e)
{
TextBox chosenDropDown = (TextBox)sender;
Int32 pickedValue = Int32.Parse(chosenDropDown.Text);

table = new Table();
table.ID = "table" + chosenDropDown.ID;
Page.Form.Controls.Add(table);
//(Table)Page.Form.FindControl("table");
//table.ID = "table" + chosenDropDown.ID;
for (int i = 1; i <= pickedValue; i++)
{
TableRow row = new TableRow();
TableCell cell = new TableCell();
cell.Attributes.Add("runat", "server");
Label txtLevel = new Label();
txtLevel.ID = "txtLevel" + i.ToString();
txtLevel.Text = "Level" + i.ToString()+" ";
txtLevel.EnableViewState = true;
cell.Controls.Add(txtLevel);
TextBox txtInterview = new TextBox();
txtInterview.ID = "txtLevel_" + i.ToString();
txtInterview.Text = "";
txtInterview.EnableViewState = true;
cell.Controls.Add(txtInterview);
row.Cells.Add(cell);
table.Rows.Add(row);
}
pnlInterview.Visible = true;
pnlInterview.Controls.Add(table);
}
ali tuncer10y ago
could be related to css, or you might be creating them in a wrong place(could be wrong div,table,td..), if functionality is working, that part should be easier!
Phani Kumar10y ago
Hi Ali,

I have modified my part of code then it worked, but here I got another problem is text boxes which were given dynamic those were displayed in the bottom of page, they are not coming in the part where i wanted them
ali tuncer10y ago
Hi Phani,
I didn't realize you were using master page, it is looking for a table in master page..
you don't need that line, you already defined a table with id "table" in aspx code..delete that line, it will build..
Phani Kumar10y ago
Hi Ali,

I have modified the mentioned as suggested by you but it doesn't worked, still getting null value for table
Phani Kumar10y ago
but we need to give id for table, how to give it then
ali tuncer10y ago
Hi Phani,
That's the problem, you are trying to add rows to a table with id "tabletxtRoundNumber" in your page but it doesn't exist. You need to fix that part..you should look for a table id that exist in the page..
Phani Kumar10y ago
Hi Ali,

it is returning null
Amit Kumar10y ago
Hi Dear,
Please open this link In hope your problem will resolve..

http://www.dotnetcurry.com/ShowArticle.aspx?ID=135
ali tuncer10y ago
What does this line return? is it null? Probably this part has problem..
Table table = // new Table();
(Table)Page.Form.FindControl("table" + chosenDropDown.ID);

if you change like this, I don't think you will receive "object reference not set to an object" error:

Table table = // new Table();
(Table)Page.Form.FindControl("table");
Phani Kumar10y ago
Hi Lizard,

Here I am adding my piece of code

In aspx.cs page :

protected void txtRoundNumber_TextChanged(object sender, EventArgs e)
{
TextBox chosenDropDown = (TextBox)sender;
Int32 pickedValue = Int32.Parse(chosenDropDown.Text);
Table table = // new Table();
(Table)Page.Form.FindControl("table" + chosenDropDown.ID);
for (int i = 0; i < pickedValue; i++)
{
TableRow row = new TableRow();
TableCell cell = new TableCell();
TableCell cell1 = new TableCell();
//cell1.Attributes.Add("runat", "server");
cell.Attributes.Add("runat", "server");
Label txtLevel = new Label();
TextBox txtInterview = new TextBox();
txtLevel.ID = "txtLevel" + i.ToString();
txtLevel.Text = "InterviewLevel" + i.ToString();
txtLevel.EnableViewState = true;
txtInterview.ID = "txtLevel_" + i.ToString();
//txtInterview.Text = "";
txtInterview.EnableViewState = true;
//cell1.Controls.Add(txtLevel);
cell.Controls.Add(txtInterview);
row.Cells.Add(cell);
//row.Cells.Add(cell1);
table.Rows.Add(row);
}
}

In aspx. page :

*

CssClass="failureNotification" ErrorMessage="Please Select Module"
ValidationGroup="IRM" ForeColor="Red">

*

CssClass="failureNotification" ErrorMessage="Please Enter Number of Rounds of Interview"
ValidationGroup="IRM" ForeColor="Red">

I am unable to know where I went wrong
Phani Kumar10y ago
i don't want 5 rows of text boxes

My form is interview round configuration

Here I will enter number of rounds of interview then I need to display dynamic text boxes with label as level1 opp to that user can enter 1st level interview round name in text box. in this format what was the user enter the number that many text boxes to be displayed with level numbers.
Phani Kumar10y ago
Hi Lizard
thanks for your reply, the error which I am getting is while adding row to table, then I am getting object reference not set to an object, I am getting NULL reference there
theLizard10y ago
You have not told us what the error is so can only guess.
You have not told us if the text box is an asp:TextBox or a plain Input TextBox.
You have not told us what you want to do with the text boxes after they are created.

The following is a simple implementation of what you want,

In Master Page Code file

protected void Button1_Click(object sender, EventArgs e)
{
int boxes=0, rows = 0, i=0, t=1, perrow = 0, k=0;
decimal j = 0;

int.TryParse(TextBox2.Text, out perrow);

int.TryParse(TextBox1.Text, out boxes);
string s = "";
j = boxes;

if ( j % perrow != 0)
{
rows = (int)j/perrow + 1;
}
else
rows = (int)j / perrow;

for (i = 0; i < rows; i++)
{
s += "";
for (k = 0; k < perrow; k++)
{
s = AddRow(s, t);
t++;
boxes--;
if (boxes == 0)
break;
}
if (k % perrow == 0)
s += "";
}
s += "

";

TableDiv.InnerHtml = s;
}
private string AddRow(string s, int t)
{
s += "Label" + t.ToString() + "";
s += "";
return (s);
}

In Master Page

<%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage" %>

Num Text Boxes Text Boxes each Row

Num Text Boxes	Text Boxes each Row