Dynamic ID (runtime)

Dear all,
I am trying to use DataList with RepeatColumn property. How to assign dynamic IDs to my image control?

It doesn't work if I assign it like this:

     <asp:Image ID='<%# Eval("Product_ID") %>' runat="server" ImageUrl='<%# "~/images/" & Eval("Image_URL") %>' />
Below is the code:

<asp:DataList ID="Product" runat="server" RepeatColumns="2">
  <ItemTemplate>
    <asp:Image runat="server" ImageUrl='<%# "~/images/" & Eval("Image_URL") %>' />
  </ItemTemplate>
</asp:DataList>
 
Thanks in advance
Keiko

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