Drilling down a nested master page in ASP.NET to reset a form

Here is an example of drilling down a master page in ASP.NET to reset a form's TextBox controls:

    protected void btnqReset_Click(object sender, EventArgs e)
    {

        try
        {
            ContentPlaceHolder childMasterContent = (ContentPlaceHolder)Page.Form.FindControl("ParentMasterContent").FindControl("ChildMasterContent");
            Control ctrlForm = childMasterContent.FindControl("upnlQueryMoreCriteria").FindControl("pnlQueryMoreCriteria");
            Control[] queryControls = { ctrlForm };
            for (int i = 0; i < 1; i++)
            {
                if (queryControls[i].Controls != null)
                {
                    foreach (Control ct in queryControls[i].Controls)
                    {
                        if (ct.GetType().ToString().Equals("System.Web.UI.WebControls.TextBox"))
                        {
                            ((TextBox)ct).Text = "";
                        }
                    }
                }
            }
        }
        catch (Exception ex)
        {
            log.Error("Unable to reset query criteria: " + ex.Message + ex.StackTrace);
            
        }
    }