Moving item from listbox

In your .aspx page add three listboxes and name it to lbx1,lbx2 and lbx3.
Add two buttons btnforward n btnbackward.
Write a function to fetch data from database

public DataTable adddata()
    {
        try
        {
            if (con.State == ConnectionState.Closed)
            {
                con.Open();
            }
            string str = "select loguser from OrderStatususermaster where userid<'10'";
            cmd = new SqlCommand(str, con);
            da = new SqlDataAdapter(cmd);
            dt = new DataTable();
            da.Fill(dt);
            return dt;
        }
        finally
        {
            if (con.State == ConnectionState.Open)
            {
                con.Close();
            }
        }
    }

In page load method add

if (!IsPostBack)
      {
          DataTable dt1 = adddata();
          for (int i = 0; i < dt1.Rows.Count; i++)
          {
              lbx1.Items.Add(dt1.Rows[i]["loguser"].ToString().Trim());
              lbx2.Items.Add(dt1.Rows[i]["loguser"].ToString().Trim());
              lbx3.Items.Add(dt1.Rows[i]["loguser"].ToString().Trim());
          }
          GridView1.DataSource = dt;
          GridView1.DataBind();
      }

In BtnForward click lbx1 selected item added to lbx3 and removed from lbx1 and lbx2

protected void btnforward_Click(object sender, EventArgs e)
   {
       string s1 = lbx1.SelectedItem.Text.Trim();
       lbx1.Items.Remove(s1);
       lbx2.Items.Remove(s1);
       lbx3.Items.Add(s1);
   }

In BtnBackward Click Method lbx3 selected item will be added to lbx1 and lbx2 as they
were appear at same position:-

protected void btnbackward_Click(object sender, EventArgs e)
   {
       string s1 = lbx3.SelectedItem.Text.Trim();
       int index = 0;
       DataTable dt1 = new DataTable();
       dt1 = adddata();
       for (int i = 0; i < dt1.Rows.Count; i++)
       {
           if (dt1.Rows[i]["loguser"].ToString().Trim() == s1)
               index = i;
       }
       lbx3.Items.Remove(s1);
       if (index < lbx1.Items.Count)
       {
           lbx1.Items.Insert(index, s1);
           lbx2.Items.Insert(index, s1);
       }
       else
       {
           lbx1.Items.Add(s1);
           lbx2.Items.Add(s1);
       }
   }

Thank You!!!