Private dt As New DataTable
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles MyBase.Load
        dt.Columns.Add("prim", GetType(Integer))
        dt.Columns.Add("Land", GetType(String))
 
        For i As Integer = 1 To 10
            dt.Rows.Add(i, "Land " & i)
        Next
 
        With Me.ComboBox1
            .DataSource = dt
            .ValueMember = "Prim"
            .DisplayMember = "Land"
        End With
    End Sub
 
    Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, _
      ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
        Me.TextBox1.Text = Me.ComboBox1.SelectedIndex
    End Sub