programmatically added click event in user control won't fire - asp.net

Question

I'm having issues getting the click event for a button contained within a programmatically added user control to fire. I understand that the event must be wired up each time a new user control is added, and I'm pretty sure I'm doing that, but still nothing. The click event for the button works fine for the first user control, which is not added programmatically. Here's the markup for the user control....
<asp:Panel ID="pnlAddressForm" runat="server">
<asp:Label ID="lblStreet" runat="server" Text="Street Address"></asp:Label>
<asp:TextBox ID="txtStreet" runat="server"></asp:TextBox>
<br /><br />
<asp:Label ID="lblCity" runat="server" Text="City"></asp:Label>
<asp:TextBox ID="txtCity" runat="server"></asp:TextBox>
<br /><br />
<asp:Label ID="lblState" runat="server" Text="State"></asp:Label>
<asp:TextBox ID="txtState" runat="server"></asp:TextBox>
<br /><br />
<asp:Label ID="lblZip" runat="server" Text="Zip"></asp:Label>
<asp:TextBox ID="txtZip" runat="server"></asp:TextBox>
<br /><br />
<asp:Button ID="btnRemoveAddress" runat="server" Text="Remove Address" OnClick="btnRemoveAddress_Click" />
</asp:Panel>
...and here's the markup for the main page...
<form id="form1" runat="server">
<div>
<My:FormUserControl runat="server" ID="myFormUserControl" />
<br /><br />
<hr />
<My:AddressUserControl runat="server" ID="myAddressUserControl" />
<br /><br />
<asp:PlaceHolder ID="phAddresses" runat="server"></asp:PlaceHolder>
<br /><br />
<asp:Button ID="btnAddAddress" runat="server" Text="Add Another Address" OnClick="btnAddAddress_Click" />
</div>
<br /><br />
<hr />
<asp:Button ID="btnSubmit" runat="server" Text="Create PDF" OnClick="btnSubmit_Click" />
</form>
..as you can see it already contains one AddressUserControl declaratively. All subsequent AddressUserControls are added to phAddresses once btnAddAddress is clicked. AddressUserControls are added this way in the code behind...
private static List<AddressUserControl> addresses = new List<AddressUserControl>();
protected void Page_PreInit(object sender, EventArgs e)
{
int addressCount = 0;
foreach (AddressUserControl aCntrl in addresses)
{
Literal ltlSpace = new Literal();
ltlSpace.Text = "<br /><br />";
phAddresses.Controls.Add(aCntrl);
phAddresses.Controls.Add(ltlSpace);
addressCount++;
}
}
When btnAddAddress is click this event handler runs...
protected void btnAddAddress_Click(object sender, EventArgs e)
{
AddressUserControl aCntrl = LoadControl("~/UserControls/AddressUserControl.ascx") as AddressUserControl;
findAddressControlRemoveButton(aCntrl);
addressUserControlButton.ID = "btnRemoveAddress" + addresses.Count + 1;
addressUserControlButton.Click += new EventHandler(addressUserControlButton_Click);
addresses.Add(aCntrl);
}
...and here's the addressUserControlButton event handler. This never runs, I suppose I'm not adding it correctly in the above handler?
private void addressUserControlButton_Click(object sender, EventArgs e)
{
Button thisButton = sender as Button;
thisButton.Text = "Why Hello";
}
EDIT - Ok, so I moved the eventhandler assignment to Page_PreInit instead of within btnAddAddress_Click, like so....
protected void Page_PreInit(object sender, EventArgs e)
{
int addressCount = 0;
foreach (AddressUserControl aCntrl in addresses)
{
Literal ltlSpace = new Literal();
ltlSpace.Text = "<br /><br />";
phAddresses.Controls.Add(aCntrl);
findAddressControlRemoveButton(aCntrl);
addressUserControlButton.ID = "btnRemoveAddress" + addressCount;
addressUserControlButton.Click += new EventHandler(addressUserControlButton_Click);
phAddresses.Controls.Add(ltlSpace);
addressCount++;
}
}
Not totally clear on why or how this fixed the problem though.

Answer 1

When you add any control programmatically, you need to register click event after that.