Access data from dynamically created controls

Question

I'm working on a report management system. Each report has its own parameters. Parameter names and saved values are kept in the database.

When the user selects a report from a GridView, the parameter names and values are dynamically created like so. Note that during development, I'm just adding a Label for the Parameter Name and a Textbox for the Parameter Value. In its final version, there will be several different types of Parameter Value controls (e.g., DropDownList, ListBox, Calendar).

DataSet ds = dal.GetSavedParameters(reportID);

for (int i = 0; i < ds.Tables[0].Rows.Count; i++)
{
        DataRow dr = ds.Tables[0].Rows[i];
        Label lbl = new Label();
        Literal ltl = new Literal();
        ltl.ID = "ltl" + i.ToString();
        lbl.ID = "lbl" + i.ToString();
        lbl.Text = dr["ParameterName"].ToString();
        TextBox txt = new TextBox();
        txt.ID = "parm" + i.ToString();          // any control will have the ID "parm" + i, not just TextBoxes
        txt.Text = dr["ParameterValue"].ToString();
        pnlParameters.Controls.Add(lbl);        // an asp:Panel
        pnlParameters.Controls.Add(txt);
        pnlParameters.Controls.Add(ltl);         // to add a line break between parameter name/value pairs
}

This will create dynamic controls named "lbl0", "ltl0", "parm0", "lbl1", "ltl1", "parm1", etc.

Now when it's time to Update the Parameters (i.e., the user has decided to store different values for this report). I can't find the Labels or Textboxes. I've used some of the following:

DataSet ds = dal.GetSavedParameters(reportID);        // get the stored values for update later

DataTable dt = ds.Tables[0];

foreach(DataRow row in dt.Rows)
{
        for (int i = 0; i < dt.Rows.Count; i++)
        {
                string labelName = "lbl" + i.ToString();
                string valueName = "parm" + i.ToString();

                Label lblName = new Label();
                lblName = (Label)pnlParameters.FindControl(labelName);
...
}

lblName keeps coming back "null". By the way, if I use the name of a "real" label (e.g., "lblTest"), this word just fine.

I've also tried a helper method:

private static Control Find(Control C, string ControlName)
{
        if (C.ID == ControlName) return C;

        foreach(Control c in C.Controls)
        {
                Control cntrl = Find(c, ControlName);
                if (cntrl != null) return c;
        }        
        return null
}

This is called as:

Label lblName = (Label)Find(pnlParameters, labelName);

Label still comes back null.

Any ideas?

TIA,
Michell