First of all, you need to create two tables:
Positions
Employees
Create a one-to-many relation between these tables as shown in the picture below:
Now, open the Visual Studio .NET, create a new Windows Application solution in VB.NET. Add a form to this project.
Add the following controls to the form:
TreeView, name it as tv
Label, name it as lblShow
Switch to the View Code mode, and add the Data.OleDb namespace at the top of the document:
Imports System.Data.OleDb
and the code:
Sub BindTreeView()
Dim pkp(0), pke(0) As DataColumn
Dim dtPositions, dtEmployees As New DataTable
Dim strconn As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\Power\Desktop\db.mdb"
Dim conn As OleDbConnection
Dim da As OleDbDataAdapter
Dim i As Integer
Dim j As Integer
Try
'Initialize connection
conn = New OleDbConnection(strconn)
' Bind the Positions DataTable dtPositions
da = New OleDbDataAdapter("Select * from Positions", conn)
dtPositions.Clear()
da.Fill(dtPositions)
pke(0) = dtPositions.Columns("ID")
dtPositions.PrimaryKey = pke
' Bind the Employees DataTable dtEmployees
da = New OleDbDataAdapter("Select * from Employees", conn)
dtEmployees.Clear()
da.Fill(dtEmployees)
pke(0) = dtEmployees.Columns("ID")
dtEmployees.PrimaryKey = pke
conn.Close()
' Loop throught dtPosition
For i = 0 To dtPositions.Rows.Count - 1
'Add parent Node
tv.Nodes.Add(dtPositions.Rows(i).Item("Position"))
' Loop throught dtEmployees
For j = 0 To dtEmployees.Rows.Count - 1
' Check if employee belongs to positions
If dtPositions.Rows(i).Item("ID") = dtEmployees.Rows(j).Item("PositionID") Then
'Add employees to parent node
tv.Nodes(i).Nodes.Add(dtEmployees.Rows(j).Item("Name"))
End If
Next
Next
Catch ex As Exception
MsgBox(ex.Message)
End Try
End Sub
Happy Coding!
