Question: In asp.net, buttons can have postback urls (ie by specifying a PostBackUrl - I have used this to truncate querystring parameters in the past - by just specifying the page url without any parameters). This is super easy with a button.

Does anyone know what the best approach to doing this is with a dropdownlist? If I specify AutoPostBack (post back when the selection changes), there doesn't seem to be an easy way to modify the postback url (ie postback to the page without querystring parameters).

I'm guessing maybe doing a custom postback with javascript... but is there a better method - like a property as in the asp.net button that I am missing?

Answer: 
No there isn't property with DropDownList. You can redirect the user using `Response.Redirect` method and use `Session collection` to persists data between requests.
If you are wanting to POST directly to another page, use could try a hidden button approach

```
<asp:DropDownList ID="lstMyDropDown" runat="server"  ClientIDMode="Static" onchange="javascript:$get('btnHidden').click(); ">
    <asp:ListItem Value="0" Text="Some Value 1" />
    <asp:ListItem Value="1" Text="Some Value 2" />
</asp:DropDownList>
<asp:Button ID="btnHidden" runat="server" ClientIDMode="Static" PostBackUrl="~/myProcessingPage.aspx" OnClientClick="javascript:if($get('lstPrinterModel').selectedIndex < 1){return false;}" style="display:none"  />

```