Default text for empty Repeater control
Joaos answer can even be simplified. In the footer, do not set the visible-property of your default item to false, but use the following expression:
<FooterTemplate> <asp:Label ID="defaultItem" runat="server" Visible='<%# YourRepeater.Items.Count == 0 %>' Text="No items found" /></FooterTemplate>This way, you can save the code behind.
Another possibility:
<FooterTemplate> <asp:Label ID="lblEmptyData" runat="server" Visible='<%# ((Repeater)Container.NamingContainer).Items.Count == 0 %>' Text="No items found" /></FooterTemplate>The benefit of this code snippet is that you aren't dependent on the ID you assigned to your repeater.
You could workaround the fact that Repeater does not support a inbuilt way to accomplish what you are doing by using the FooterTemplate in conjunction with the OnItemDataBound event and showing the footer only when the data source returns no items.
Examples on how you can do this can be found at: