Hi Karl-Inge,
No, it is not exactly basic information that you missed; rather it is
programming knowledge that you would have acquired had you worked with DHTML
before the ASP.NET server controls had come along.
ASP.NET server controls are very excellent creatures in allowing programmers
powerful interfaces without having to learn all of the details of the HTML
objects that they render. The onmouseover and onmouseout attributes could
have been done in a more elegant manner without having the intellisense
complaining about them like this in the codebehind (e.g. during the Page
PreRender event handling):
Button1.Attributes.Add("onmouseover", "this.className='class1';")
Button2.Attributes.Add("onmouseout", "this.className='class2';")