Dynamic menu in ASP.net

Step 3: Write the code for binding asp.net menu on basis of category like this

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Data.SqlClient;
using System.Data;

public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
populateMenuItem();
}
}
private void populateMenuItem()
{
DataTable menuData = GetMenuData();
AddTopMenuItems(menuData);
}
private DataTable GetMenuData()
{
using (SqlConnection con = new SqlConnection("Data Source=.\\SQLEXPRESS;AttachDbFilename=|DataDirectory|\\Database.mdf;Integrated Security=True;User Instance=True"))
{
using (SqlCommand cmd = new SqlCommand("SELECT Id,ParentId,Name FROM tblProduct", con))
{
SqlDataAdapter da = new SqlDataAdapter(cmd);
DataTable dt = new DataTable();
da.Fill(dt);
return dt;
}
}
}
/// Filter the data to get only the rows that have a
/// null ParentID (This will come on the top-level menu items)
private void AddTopMenuItems(DataTable menuData)
{
DataView view = new DataView(menuData);
view.RowFilter = "ParentID IS NULL";
foreach (DataRowView row in view)
{
MenuItem newMenuItem = new MenuItem(row["Name"].ToString(), row["Id"].ToString());
Menu1.Items.Add(newMenuItem);
AddChildMenuItems(menuData, newMenuItem);
}
}
//This code is used to recursively add child menu items by filtering by ParentID
private void AddChildMenuItems(DataTable menuData, MenuItem parentMenuItem)
{
DataView view = new DataView(menuData);
view.RowFilter = "ParentID=" + parentMenuItem.Value;
foreach (DataRowView row in view)
{
MenuItem newMenuItem = new MenuItem(row["Name"].ToString(), row["Id"].ToString());
parentMenuItem.ChildItems.Add(newMenuItem);
AddChildMenuItems(menuData, newMenuItem);
}
}
}