Hi Imar,

In the code on page 548, there are two LoginStatus controls with the same ID. I have tried the code and did not get any error messages. Is it generally OK to have multiple LoginStatus controls with the same ID in the same file? If so, are there any other controls for which it would be OK too? Does the requirement for the uniqueness of IDs on a page only apply to HTML elements?

Thank you for your trouble.

Roman

Hi Roman,

Control IDs must be unique within their "naming container". Normally, the Page is the default container, so within each page the controls must have unique IDs.

The code on page 548 shows a LoginView control with different templates that define new naming containers. Since only one template can be active at any time, you can reuse the control IDs. When logged in you get LoginStatus1 from the RoleGroups element, otherwise you get the one from the LoggedInTemplate.

Hope this helps,

Imar

---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of Beginning ASP.NET 3.5 : in C# and VB, ASP.NET 2.0 Instant Results and Dreamweaver MX 2004
Want to be my colleague? Then check out this post.

Thank you, Imar. That makes sense. Cheers, Roman.

Imar,

I started to write a response very similar to yours but then wasn't sure if I was right. Aren't all controls that can contain other controls naming containers? Are the templates of templated controls naming containers as well? I have used the same technique you demonstrate several times without problems.

-Peter
compiledthoughts.com

Yes, AFAIK, all controls that can contain other controls are naming containers.

I am not 100% sure about templates. Maybe .NET internally knows only one of them can be active at any time and doesn't bother with IDs there.
The net effect is the same though: you can't use multiple controls within a container. ASP.NET must always be able to create unique controls like ParentId_FirstChildId_SecondChildId and so on.

Imar


---------------------------------------
Imar Spaanjaars
http://Imar.Spaanjaars.Com
Everyone is unique, except for me.
Author of Beginning ASP.NET 3.5 : in C# and VB, ASP.NET 2.0 Instant Results and Dreamweaver MX 2004
Want to be my colleague? Then check out this post.