[E100]

كود :

Imports System.Data.OleDb

Public Class Form1
   Dim conne As String = "Provider=Microsoft.jet.OLEDB.4.0;Data Source=" & Application.StartupPath & "\Database1.mdb"
   Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
       fill_father_name()
   End Sub
   Private Sub fill_father_name()

  Dim SQL As String = "SELECT Fathercode , Fathername From TableFather"
       Dim da As New OleDbDataAdapter(SQL, conne)
       Dim ds As New DataSet
       da.Fill(ds, "TableFather")
       ComboBox1.DataSource = ds.Tables("TableFather")
       ComboBox1.DisplayMember = "Fathername"
       ComboBox1.ValueMember = "Fathercode"
       ComboBox1.SelectedIndex = -1
   End Sub
   Private Sub fill_student_name()
       Dim SQL As String = "SELECT studentname , studentfathercode From TableStudent Where studentfathercode = '" & ComboBox1.SelectedValue & "'"
       Dim da As New OleDbDataAdapter(SQL, conne)
       Dim ds As New DataSet
       da.Fill(ds, "TableStudent")
       ComboBox2.DataSource = ds.Tables("TableStudent")
       ComboBox2.DisplayMember = "studentname"
       ComboBox2.ValueMember = "studentfathercode"
   End Sub
   Private Sub ComboBox1_SelectionChangeCommitted(sender As Object, e As System.EventArgs) Handles ComboBox1.SelectionChangeCommitted
       fill_student_name()
   End Sub

 
End Class