Private Class xxx
        Public s As String
        Public i As Integer
    End Class
 
    Private Sub Test()
        Dim xxx1 As New xxx
        xxx1.s = "Hey!"
        xxx1.i = 99
 
        Dim t As Type = xxx1.GetType()
 
        For Each fi As Reflection.FieldInfo In t.GetFields( _
          Reflection.BindingFlags.Public Or Reflection.BindingFlags.Instance)
            Debug.WriteLine(fi.Name + " / " + fi.FieldType.ToString() + " / " + _
            fi.GetValue(xxx1).ToString())
            If fi.FieldType Is GetType(System.String) Then
                fi.SetValue(xxx1, "New Data")
            Else
                fi.SetValue(xxx1, 123)
            End If
        Next
 
    End Sub