Develop Reference

How to edit a control content in an array inside of a list

I got the following:
List<TextBox[]> ListMonths = new List<TextBox[]>();
I use it for store the same textboxes for each month, I fill it like this
for (int i = 0; i <= 11; i++)
{
......
TextBox[] TBaux = new TextBox[18];
for (int o = 0; o <= 17; o++)
{
TBaux[o] = (TextBox)element.FindName("TB" + o + i);
}
ListMonths.Add(TBaux);
}
So that way I got the textboxes for each month in ListMonths.
How can I modify the Text property of one of the textbox (for instance textbox[2]) that is stored in one of the month lists (for instance ListMonths[1])?

ListMonths[1][2].Text = "blabla";
Which is the same as doing:
TextBox[] textBoxes = ListMonths[1];
TextBox textBox = textBoxes[2];
textBox.Text = "blabla";

How to access value of an ASP textbox that contains variable in its ID

I am creating a total of n textbox whenever i enter the value n on a textbox and click on a button in ASP.NET. Im using the below code for that,
int n = Convert.ToInt32(text_flats_blocks.Text);
for (int i = 0; i < n; i++)
{
TextBox MyTextBox = new TextBox();
MyTextBox.ID = "text_" + (i+1);
panel_flats_blocks.Controls.Add(MyTextBox);
MyTextBox.CssClass = "textblock";
Literal lit = new Literal();
lit.Text = "<br /><br />";
panel_flats_blocks.Controls.Add(lit);
}
This works fine and the textboxes are created. Then i enter some values to the textboxes and click on another button. On clicking the second button the values entered in the textboxes should be obtained using C#. But i have created ID for these textboxes using variables like this text_ + (i+1) that creates the names as text_1, text_2 etc. How can i use this as an ID to access the textbox value like id.Text but here the id contains variable. I want to use loop to iterate for n times and access all values from all n textboxes and store them in a list. How can i do this using C#?

You can use FindControl Method
public void SecondButton_Click(object sender, EventArgs)
{
int n = Convert.ToInt32(text_flats_blocks.Text);
for (int i = 0; i < n; i++)
{
var control= (TextBox)FindControl("text_" + (i+1));
//now you have the controls and you can do whatever you want with them
}
}

get value of dynamically created textboxes

ASP.NET C#.
Inside UpdatePanel we have TextBox with OnTextChanged="text_changed" method and Panel.
if number 3 was typed at textbox, 3 textboxes below will appear inside Panel with different IDs.
However when button outside updatepanel clicks, dynamically created textboxes not found error occured.
How to get values of dynamically created textboxes?
Creating textbox:
protected void text_changed(Object sender, EventArgs e)
{
int n = Int32.Parse(TextBox6.Text);
Table table = new Table();
for (int i = 0; i < n; i++)
{
TableRow trow = new TableRow();
table.Rows.Add(trow);
TableCell tcell = new TableCell();
tcell.Text = (i + 1).ToString();
TextBox tb = new TextBox();
tb.ID = "TB" + i.ToString();
tcell.Controls.Add(tb);
trow.Cells.Add(tcell);
}
Panel1.Controls.Add(table);
ButtonClick //get values from created textboxes:
int n = Int32.Parse(TextBox6.Text);
for (int i = 0; i < n; i++)
{
string title = ((TextBox)UpdatePanel1.FindControl("Panel1").FindControl("TB" + i.ToString())).Text; //here null pointer exception..
}

where are you generating your textboxes? if you're creating them in text_changed event, then on the next post back your going to run into pagelife cycle issues. you'd need to cache the fact that you created them, and recreate them in the OnInit phase of the page.

How can I use text property of dynamic created textfield?

I have this code, which dynamically creates some textfields for me. k is taken from user btw.
for (int i = 0; i < k; i++)
{
TextBox t1 = new TextBox();
t1.Parent = groupBox2;
t1.Left = textBox2.Left;
t1.Top = textBox2.Top + (i + 1) * 40;
t1.Name = "text" + (i + 1);
t1.Enabled = true;
groupBox2.Controls.Add(t1);
}
What i want to do is, after this creating phase is done, when the user presses groupbox2's "OK" button, I want to take the created textfields' text properties, but so far I don't know how could this be done, since I gave textfields a name, I tried this but didn't work.
private void button3_Click(object sender, EventArgs e)
{
node1.name = textBox2.Text;
for (int i = 0; i < k; i++)
{
node1.array[i] = Convert.ToInt32("text"+(i+1).Text);
}
}
Any help would be nice, thanks.

Try this method:
private void button3_Click(object sender, EventArgs e)
{
node1.name = textBox2.Text;
for (int i = 0; i < k; i++)
{
TextBox txtBox = (TextBox)groupBox2.FindControl("text" + (i + 1));
if (txtBox != null)
{
node1.array[i] = txtBox.Text;
}
}
}

Loop through your text boxes in groupBox1 and get their names,Try this:
List<string> TextBoxesName=new List<string>();
foreach (Control item in groupBox1.Controls)
{
if (item is TextBox)
{
TextBoxesName.Add((item as TextBox).Text);
}
}

Set to your dynamic texboxes ID and than you can do groupBox2.FindControl("dynamic_texbox_id") to get your text box

Easiest solution is to put your listboxes in a collection of some sort
List<ListBox> listboxes = new List<ListBox>();
for (...)
{
...
listboxes.add(listbox);
}
Then you can refer back to them whenever you want
Or since you're adding them to a groupbox, why not go through that collection?

dynamic text box and append and save them to sql server DataBase

HI I have requirement that
1) display given no.of textboxes dynamically and save to DB
2) if I change the number then new textboxes should append to UI
EX: TextBox AddButton
If I give 2 in textbox and click on add
Then 2 textboxes should appear. I filled some data in those textboxes. Now When I change the value 2 to 5 then 3 more textboxes should append(condition:old textboxes data should retain)
If the second value is less than or equal to first value then do nothing.
My code is
void Append()
{
string Data = string.Empty;
TextBox tb;
if (Convert.ToInt32(hdnCnt.Value) < Convert.ToInt32(txtNoofGames.Text))
{
for (int i = 0; i < Convert.ToInt16(txtNoofGames.Text); i++)
{
if (i <= Convert.ToInt32(hdnCnt.Value))
{
tb = (TextBox)Form.FindControl("txtGame1");
Data = tb.Text;
}
TextBox Newtb = new TextBox();
Newtb.ID = "txtGame" + i;
Form.Controls.Add(Newtb);
if (i <= Convert.ToInt32(hdnCnt.Value))
{
Newtb.Text = Data;
}
}
}
}
protected void btnAdd_Click(object sender, EventArgs e)
{
if (hdnCnt.Value != "")
Append();
hdnCnt.Value = txtNoofGames.Text;
for (int i = 0; i < Convert.ToInt16(txtNoofGames.Text); i++)
{
TextBox tb = new TextBox();
tb.ID = "txtGame" + i;
Form.Controls.Add(tb);
}
}
I am getting exception "object reference not set to an instance of object" at Data = tb.Text; in append method.

You didn't initialize it from the looks of it
TextBox tb = new TextBox();
Hope that helps,

Instead of Form.Controls.Add(tb);
Please try with Page.Form.Controls.Add(tb);