Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

            DBConn.Open()

'Create DataAdaptor for Customers and Orders

'Table and fetch record from the Database

Dim DBCustAdap As New SqlDataAdapter("Select * From Customers", DBConn)

Dim DBOrdAdap As New SqlDataAdapter("Select * From Orders", DBConn)

'Create DataSet object and fill DataAdapter

Dim DSCustOrder As DataSet = New DataSet

DBCustAdap.Fill(DSCustOrder, "Customers")

DBOrdAdap.Fill(DSCustOrder, "Orders")

'Add Realation using Relation Attribute

DSCustOrder.Relations.Add("CustomerOrders", DSCustOrder.Tables("Customers").Columns("CustomerID"), DSCustOrder.Tables("Orders").Columns("CustomerID"))

'Fill the TreeView control Nodes using For Loop

For Each PRow As DataRow In DSCustOrder.Tables("Customers").Rows

      Dim PNode As New TreeNode(PRow("ContactName"))

      Me.tvDisplayRecord.Nodes.Add(PNode)

For Each CRow As DataRow In PRow.GetChildRows("CustomerOrders")

PNode.ChildNodes.Add(New TreeNode(CRow("OrderID")))

Next

PNode.CollapseAll()

Next

'Close Connection and Dispose all database objects

DBCustAdap.Dispose()

DBCustAdap = Nothing

DBOrdAdap.Dispose()

DBOrdAdap = Nothing

DBConn.Close()

DBConn = Nothing

End Sub