Just tweak your existing code to:
<asp:DataList ID="dlistDetails" runat="server" DataKeyField="KeyID"
RepeatColumns="3" Width="100%"
AlternatingItemStyle-BackColor="Wheat" CaptionAlign="Top">
<ItemTemplate>
<asp:Label ID="lbl" runat="server" Text='<%# Eval("Name1") + "(" + Eval("Name2") + ")"%>' />
</ItemTemplate>
</asp:DataList>