Dynamic buttons not firing

<table border="1" cellpadding="0" cellspacing="0" id="tblGenerate" runat="server">
        <tr>
          <td>
              <asp:Label ID="lblName" runat="server" Text="Name"></asp:Label>
          </td>
          <td>
              <asp:TextBox ID="txtName" runat="server"></asp:TextBox>
          </td>
          <td>
              <asp:Button ID="btnAdd" runat="server" Text="Add New" OnClick="btnAdd_Click"/>
          </td>
          <td>
              <asp:Label ID="lblCost" runat="server"></asp:Label>
          </td>
      </tr>
      <tr>
          <td  id="trGenerate" runat="server" colspan="3">
          </td>
      </tr>
  </table>

protected void Page_Load(object sender, EventArgs e)
        {
 
        }

        protected void Page_Init(object sender, EventArgs e)
        {
            //Recreate Controls
            RecreateControls("lblName", "Label");
            RecreateControls("txtValue", "TextBox");
            RecreateControls("btnAddNew", "Button");
        }

        protected void btnAdd_Click(object sender, EventArgs e)
        {
            int cnt = FindOccurence("txtValue");

            CreateLabel("lblName_" + Convert.ToString(cnt + 1));
            CreateTextBox("txtValue_" + Convert.ToString(cnt + 1));
            CreateButton("btnAddNew_" + Convert.ToString(cnt + 1));



            //ClientScript.RegisterClientScriptBlock(this.GetType(), "Alert",

            //             "<script type = 'text/javascript'>alert('" + ID +

            //              " fired OnTextChanged event5');</script>");
        }

        private int FindOccurence(string substr)
        {

            string reqstr = Request.Form.ToString();

            return ((reqstr.Length - reqstr.Replace(substr, "").Length)

                              / substr.Length);

        }

        private void CreateTextBox(string ID)
        {
            TextBox txt = new TextBox();

            txt.ID = ID;

            trGenerate.Controls.Add(txt);

            Label lblInstance = new Label();

            lblInstance.Width = 10;

            lblInstance.Height = 20;

            trGenerate.Controls.Add(lblInstance);

        }

        private void CreateLabel(string ID)
        {
            Label lblInstance = new Label();

            lblInstance.ID = ID;

            lblInstance.Text = "Name";

            lblInstance.Width = 50;

            trGenerate.Controls.Add(lblInstance);
        }

        private void CreateButton(string ID)
        {
            Button btnAddtxt = new Button();

            btnAddtxt.ID = ID;

            btnAddtxt.Text = "Add New";

            btnAddtxt.Click += new System.EventHandler(btnAdd_Click);

            btnAddtxt.CausesValidation = true;

            trGenerate.Controls.Add(btnAddtxt);

            Literal lt = new Literal();

            lt.Text = "<br />";

            trGenerate.Controls.Add(lt);
        }

         

        private void RecreateControls(string ctrlPrefix, string ctrlType)
        {

            string[] ctrls = Request.Form.ToString().Split('&');

            int cnt = FindOccurence(ctrlPrefix);

            if (cnt > 0)
            {
                for (int k = 1; k <= cnt; k++)
                {

                    for (int i = 0; i < ctrls.Length; i++)
                    {

                        if (ctrls[i].Contains(ctrlPrefix + "-" + k.ToString())

                            && !ctrls[i].Contains("EVENTTARGET"))
                        {

                            string ctrlID = ctrls[i].Split('=')[0];



                            if (ctrlType == "TextBox")
                            {

                                CreateTextBox(ctrlID);

                            }



                            if (ctrlType == "Label")
                            {

                                CreateLabel(ctrlID);

                            }


                            if (ctrlType == "Button")
                            {
                                CreateButton(ctrlID);
                            }
                        }

                    }

                }

            }

        }
 
    }