I needed to add a DropDownList to a ASP.NET form.  Unlike forms I had used before, I wanted to make sure a different value was selected other than the top one in the list.  So, the first solution I researched was to set a default value.  This was accomplished with the Selected=”True” attribute.

The second condition I wanted to figure out was how to make sure something else besides the default value wasn’t still selected.  That was handled using a RequiredFieldValidor and setting the InitialValue field.


<asp:DropDownList ID=”dropELLIPTICALCOMETScometname” runat=”server” Width=”270px” Height=”22px”>
     <asp:ListItem Value=”Select Comet” Selected=”True”>–Select Comet–</asp:ListItem>
     <asp:ListItem Value=”Encke”>Encke</asp:ListItem>
     <asp:ListItem Value=”Halley”>Halley</asp:ListItem>
</asp:DropDownList>

<asp:RequiredFieldValidator ID=”RequiredFieldValidator9″ runat=”server” ControlToValidate=”dropELLIPTICALCOMETScometname” CssClass=”ErrorMessage” Display=”Dynamic” ErrorMessage=”Select Comet Name” InitialValue=”Select Comet”></asp:RequiredFieldValidator>

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