ต้องการดึงข้อมูลจาก Combobox ไปแสดงบน textbox เพิ่มอีก ต้องแก้เป็นอะไรครับในโค๊ด

Private Sub cbb_select_bank_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cbb_select_bank.SelectedIndexChanged
       TextBox1.Text = cbb_select_bank.Text 
   End Sub

    With cbb_select_bank
        .DataSource = dt
        .DisplayMember = dt.Columns.Item("banktitle").ColumnName
        .ValueMember =  dt.Columns.Item("urn").ColumnName 'สำหรับเก็บ ID /FK ไปใช้งาน

    End With

Private Sub cbb_select_bank_SelectedValueChanged(sender As Object, e As EventArgs) Handles cbb_select_bank.SelectedValueChanged
        MessageBox.Show("" & ComboBox1.SelectedValue)
        'มันจะดึงเอา "urn" มาโชว์
    End Sub

Public Class Form1



       'การจัดการมีแค่ 3 แถวนี้
        Me.ComboBox1.DataSource = Me.BankBindingSource
        Me.ComboBox1.DisplayMember = "BankName_1"
        Me.ComboBox1.ValueMember = "BankCode"

    Private Sub ComboBox1_SelectedValueChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedValueChanged
        MessageBox.Show("" & ComboBox1.SelectedValue & vbCrLf & ComboBox1.Text)
    End Sub
End Class

       Me.ComboBox1.DataSource = Me.BankBindingSource
        Me.ComboBox1.DisplayMember = "BankName_1"
        Me.ComboBox1.ValueMember = "BankCode"
       Me.ComboBox1.DataBindings.Add(New System.Windows.Forms.Binding("SelectedValue", Me.ContactlistBindingSource, "Contact_BankID", True))
'ผมทำการเพิ่มตาราง Contactlis ลงไปใน ฟอร์ม

Private Sub ComboBox1_SelectedValueChanged(sender As Object, e As EventArgs) Handles ComboBox1.SelectedValueChanged
        MessageBox.Show("" & ComboBox1.SelectedValue & vbCrLf & ComboBox1.Text)
    End Sub