I found a small problem with the master pages and themes of ASP. net2.0.

Create a master page, create a topic, and create a page A. aspx to use the topic. You can use theme = "default" on the HTML page"
In. add a text box on aspx and a verification control, such as the requiredfieldvalidator control that is not empty. Now, if you specify setfocusonerror = "true ", is to set the cursor position, and then look at. on the ASPX page, I found that the topic is missing. Haha, I don't know if it is a bug. Then I will post it to the page_preinit event to define the topic and in the web. the definition in config is OK, so
Try not to set a topic on the top of the page.