Bind (Populate) Nested ListView from database using Linq with C# and VB.Net in ASP.Net

Hi nauna,

I have created sample please take its reference and correct your code.

Database

For this example I have used of Northwind database that you can download using the link given below.

Download Northwind Database

HTML

<asp:ListView ID="lvCustomers" runat="server" OnItemDataBound="lvCustomers_ItemDataBound">
    <ItemTemplate><b>
        <asp:Label ID="lblID" Text='<%# Eval("CustomerID") %>' runat="server" /></b>
        <asp:HiddenField ID="hfCustomerID" runat="server" Value='<%# Eval("CustomerID") %>' /><br />
        <asp:ListView runat="server" ID="lvOrders" GroupPlaceholderID="orderGroupPlaceHolder"
            ItemPlaceholderID="orderItemPlaceHolder">
            <LayoutTemplate>
                <table>
                    <tr>
                        <th>Order ID</th>
                        <th>Price</th>
                    </tr>
                    <asp:PlaceHolder ID="orderGroupPlaceHolder" runat="server"></asp:PlaceHolder>
                </table>
            </LayoutTemplate>
            <GroupTemplate>
                <tr><asp:PlaceHolder ID="orderItemPlaceHolder" runat="server"></asp:PlaceHolder></tr>
            </GroupTemplate>
            <ItemTemplate>
                <td><asp:Label ID="lblID" Text='<%# Eval("OrderID") %>' runat="server" /></td>
                <td><asp:Label ID="lblPrice" Text='<%# Eval("Freight") %>' runat="server" /></td>
            </ItemTemplate>
        </asp:ListView>
    </ItemTemplate>
</asp:ListView>

Namespaces

C#

using System.Collections.Generic;
using System.Linq;
using NorthwindModel;

VB.Net

Imports System.Collections.Generic
Imports System.Linq
Imports NorthwindModel

Code

C#

protected void Page_Load(object sender, EventArgs e)
{
    if (!this.IsPostBack)
    {
        using (NorthwindEntities entities = new NorthwindEntities())
        {
            List<Customer> customers = new List<Customer>();
            customers = (from c in entities.Customers
                            select c).Take(3).ToList();
            this.lvCustomers.DataSource = customers;
            this.lvCustomers.DataBind();
        }
    }
}
    
protected void lvCustomers_ItemDataBound(object sender, ListViewItemEventArgs e)
{
    ListView lvOrders = (e.Item.FindControl("lvOrders") as ListView);
    string id = (e.Item.FindControl("hfCustomerID") as HiddenField).Value;
    using (NorthwindEntities entities = new NorthwindEntities())
    {
        List<Order> orders = new List<Order>();
        orders = (from o in entities.Orders
                    where o.CustomerID == id
                    select o).Take(2).ToList();
        lvOrders.DataSource = orders;
        lvOrders.DataBind();
    }
}

VB.Net

Protected Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load
    If Not Me.IsPostBack Then
        Using entities As NorthwindEntities = New NorthwindEntities()
            Dim customers As List(Of Customer) = New List(Of Customer)()
            customers = (From c In entities.Customers Select c).Take(3).ToList()
            Me.lvCustomers.DataSource = customers
            Me.lvCustomers.DataBind()
        End Using
    End If
End Sub

Protected Sub lvCustomers_ItemDataBound(ByVal sender As Object, ByVal e As ListViewItemEventArgs)
    Dim lvOrders As ListView = (TryCast(e.Item.FindControl("lvOrders"), ListView))
    Dim id As String = (TryCast(e.Item.FindControl("hfCustomerID"), HiddenField)).Value
    Using entities As NorthwindEntities = New NorthwindEntities()
        Dim orders As List(Of Order) = New List(Of Order)()
        orders = (From o In entities.Orders Where o.CustomerID = id Select o).Take(2).ToList()
        lvOrders.DataSource = orders
        lvOrders.DataBind()
    End Using
End Sub

Output