title: how to get value selected in dropdownlist before change was made?
body: <p>I have a dropdownlist with with a few options. When the user changes one of these options in the dropdownlist, I want to create a note. The problem is I want the note to say what change was made. So for example this code creates a note when the currency dropdownlist is changed. So if the current value is "Euro" and the user changes it to "Sterling" I want the note to say "currency changed from Euro to Sterling" etc. I know by using selectedItem I can get the new value selected, but how to I get the value that was in the dropdownlist before the change was made?</p>
  
  <pre><code>if (cust.Currency.ToString() != ddlCustomerCurrency.SelectedItem.Text)
     {
          Customer.Notes.InsertNote(cust.ID, Company.Current.CompanyID, DateTime.Now, "Currency changed from '" + /*Previous value */ + "' to '" + ddlCustomerCurrency.SelectedItem.Text + "'", CurrentUser.UserID, 1);
     }
  </code></pre>