C# - Event handler for dynamic buttons - asp.net

Question

I have a textbox and submit button created using the design mode.
When the submit button is pressed, it will retrieve the user input from the textbox and then make a query to my database.
It will then display a list of dynamic buttons according to the information retrieved from my database.
However, the event handler for the buttons does not fire when clicked. I guess my problem is the postback but I cannot create those buttons in page_load etc. because I need to get the user input (from the textbox when submit button is pressed) before i can load the buttons.
How can i solve this problem?
Thank you.
Edit (codes):
protected void subBtn_Click(object sender, EventArgs e)
{
//database setup codes
.......
while (reader.Read())
{
Button detailsBtn = new Button();
detailsBtn.Text = reader["fName"].ToString();
//doesn't fire
detailsBtn.Click += new EventHandler(detailsBtn_Click);
memPanel.Controls.Add(detailsBtn);
}
}

Answer 1

Main problem is Postback regenerate dynamic controls on each postback if those controls does not exists.
For quick demo see this code
ASPX CODE
<form id="form1" runat="server">
<asp:Button ID="Button1" runat="server" Text="Button" onclick="Button1_Click" />
<asp:Panel ID="pnl" runat="server"></asp:Panel>
</form>
ASPX.CS CODE
protected void Page_Load(object sender, EventArgs e)
{
if(IsPostBack)
{
generate();
}
}
public void generate()
{
if (!pnl.HasControls())
{
for (int i = 0; i < 4; i++)
{
Button detailsBtn = new Button();
detailsBtn.Text = "fName" + i.ToString();
detailsBtn.ID = i.ToString();
detailsBtn.Click += new EventHandler(detailsBtn_Click);
pnl.Controls.Add(detailsBtn);
}
}
}
protected void Button1_Click(object sender, EventArgs e)
{
generate();
}
protected void detailsBtn_Click(object sender, EventArgs e)
{
}

Answer 2

Sound to me like you could easily refactor your page to use a simple <asp:Repeater runat="server" ..></asp:Repeater> instead of dynamically adding controls to a Panel.
Here is a very simple complete sample:
RepeaterTest.aspx
<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="Server">
<asp:TextBox ID="theTextBox" runat="server"></asp:TextBox>
<asp:Button ID="theButton" runat="server" OnClick="theButton_Click" Text="Click me" />
<asp:Repeater ID="test" runat="server">
<ItemTemplate>
<asp:Button ID="theRepeaterButton" runat="server" Text='<%# Eval("fName") %>' OnClick="theRepeaterButton_Click" />
</ItemTemplate>
</asp:Repeater>
</asp:Content>
RepeaterTest.aspx.cs
public partial class RepeaterTest : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
}
protected void theButton_Click(object sender, EventArgs e)
{
string filter = theTextBox.Text;
// below row simulates fetching data using the filter text in the text box
var data = Enumerable.Range(0, 20).Select(i => new { fName = filter + " " + i });
test.DataSource = data;
test.DataBind();
}
protected void theRepeaterButton_Click(object sender, EventArgs e)
{
var button = (Button)sender;
// do something here based on text/commandname/commandargument etc of the button
}
}