Hi,
There are some examples on how to make dropdownlist to autopostback on change over developers web communities.
What code are you using in your form control? You could use updatepanel for that action.
Quoting some example:
<asp:ScriptManager ID="smMain" runat="server" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Always" ChildrenAsTriggers="true" >
<ContentTemplate>
<asp:DropDownList ID="DropDownList1" runat="server" AutoPostBack="True" onselectedindexchanged="DropDownList1_SelectedIndexChanged">
<asp:ListItem>item 1</asp:ListItem>
<asp:ListItem>item 2</asp:ListItem>
</asp:DropDownList>
</ContentTemplate>
</asp:UpdatePanel>
//and the handler method
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
// load the data for the second dropdown list
}
What issues are you having with your form control in particular?
Any errors or incorrect behavior?
Regards,
Zdenek