How do I create a dynamic menu and sub menu in ASP.NET using C#

hi team,

please help to correct the following code below which i have written but its giving an error of 'ds' and 'ddl' doesnt contain in the context


using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Data.Odbc;

public partial class creatmenu : System.Web.UI.Page
{
  protected void Page_Load(object sender, EventArgs e)
  {
  if (!IsPostBack)
  {
  FillddlMainMenu();

  }

  }

  public void FillddlMainMenu()
  {
  OdbcConnection conn = new OdbcConnection("dsn=parcel;uid=dba;pwd=sql");
  DataSet dsFill = new DataSet();
 
  OdbcDataAdapter OdbcDa = new OdbcDataAdapter("Select MainMenuId,MainMenu from  MainMenu", conn);

  conn.Open(); 

  OdbcDataAdapter.Fill(ds);
  ddlMainMenu.DataSource = DS;

  ddlMainMenu.DataBind();
 

  }
  protected void btnMainmenu_Click(object sender, EventArgs e)
  {
  OdbcCommand cmd;
 
  int active;
  if (chkMActive.Checked)
  {
  active = 1;
  }
  else
  {
  active = 0;
  }
  OdbcConnection conn = new OdbcConnection("dsn=parcel;uid=dba;pwd=sql");
  cmd = new OdbcCommand("INSERT INTO mainmenu(mainmenu, mcontent, menuorder,isactive)VALUES('" + txtMainmenu.Text + "','" + txtMContent.Text + "'," + Convert.ToInt16(MOrder.SelectedItem.Value) + "," + active + ")", conn);
  conn.Open();
  //cmd.CommandType = CommandType.Text;
  cmd.ExecuteNonQuery();
  conn.Close();
  FillddlMainMenu();
  Response.Redirect("creatmenu.aspx");
  }
  protected void btnSubmenu_Click(object sender, EventArgs e)
  {
  int active;
  if (chkSActive.Checked)
  {
  active = 1;
  }
  else
  {
  active = 0;
  }
  OdbcCommand cmd;
  OdbcConnection conn = new OdbcConnection("dsn=parcel;uid=dba;pwd=sql");
  cmd = new OdbcCommand("INSERT INTO submenu(submenu, content, menuorder,parentid,isactive)VALUES('" + txtSubmenu.Text + "','" + txtSContent.Text + "'," + Convert.ToInt16(ddlSOrder.SelectedItem.Value) + "," + Convert.ToInt16(ddlMainMenu.SelectedItem.Value) + "," + active + ")", conn);
 
  conn.Open();
 
  cmd.ExecuteNonQuery();
  conn.Close();
  Response.Redirect("creatmenu.aspx");
  }
}

regard
george