I want to create a Repeater that displays the header/footer based on properties, only if the DataSource
is empty.
public class Repeater : System.Web
Use ListView instead of Repeater. It already contains EmptyDataTemplate and EmptyItemTemplate elements so you don't need to do anything :)
If you want to do this with just a repeater you can do this:
<asp:Repeater runat="server" OnItemDataBound="ShowHideHeaderFooter">
<HeaderTemplate>
<asp:PlaceHolder runat="server" ID="PlaceHolderHeader">
HEADER STUFF
</asp:PlaceHolder>
</HeaderTemplate>
<ItemTemplate>
ITEM STUFF
</ItemTemplate>
<FooterTemplate>
<asp:PlaceHolder runat="server" ID="PlaceHolderFooter">
FOOTER STUFF
</asp:PlaceHolder>
</FooterTemplate>
</asp:Repeater>
and then in your code behind
protected void ShowHideHeaderFooter(object sender, RepeaterItemEventArgs e)
{
if(e.Item.ItemType == ListItemType.Header && theDataSource.Count == 0 && !ShowHeaderOnEmpty)
{
e.Item.FindControl("PlaceHolderHeader").Visible = false;
}
...
}
override the render event to output the HTML you want based on the all properties you have mentioned.
I would create a Web User Control (.ascx) that contains your header section, a [child] repeater control, and a footer section. You can put all your logic in that custom control.
[ToolboxData("<{0}:SmartRepeater runat=\"server\"></{0}:SmartRepeater>")]
public partial class SmartRepeater : Repeater
{
public bool ShowHeaderOnEmpty { get; set; }
public bool ShowFooterOnEmpty { get; set; }
private ITemplate emptyTemplate = null;
[PersistenceMode(PersistenceMode.InnerProperty)]
public ITemplate EmptyTemplate
{
get { return this.emptyTemplate; }
set { this.emptyTemplate = value; }
}
protected override void OnDataBinding(EventArgs e)
{
base.OnDataBinding(e);
if (this.Items.Count == 0)
{
this.Controls.Clear();
if (this.HeaderTemplate != null && ShowHeaderOnEmpty)
this.HeaderTemplate.InstantiateIn(this);
if (this.EmptyTemplate!=null)
this.EmptyTemplate.InstantiateIn(this);
if (this.FooterTemplate != null && ShowFooterOnEmpty)
this.FooterTemplate.InstantiateIn(this);
}
}
}
Usage:
<UC:SmartRepeater ID="rep" runat="server" ShowHeaderOnEmpty="true" ShowFooterOnEmpty="true">
<HeaderTemplate>HEADER</HeaderTemplate>
<ItemTemplate>Item</ItemTemplate>
<SeparatorTemplate>, </SeparatorTemplate>
<EmptyTemplate><b>Nothing</b></EmptyTemplate>
<FooterTemplate>FOOTER</FooterTemplate>
</UC:SmartRepeater>