Do you ever end up on an MSDN page only to realize you are looking at the wrong version of the Framework or even worse Silverlight when you need WPF 3.5? Well, things have gotten a little overwhelming since we now have 4 versions of the Framework and the Silverlight docs online. Cheryl on the Silverlight team just posted a nice blog on figuring out which documentation set you are in on MSDN online. Since they all have the same namespaces, it can get confusing fast. In addition to the info Cheryl provides, there is another clue which might help you with search results.
Here is an example search for Button.
Notice the URL for the page (#1). If you are looking for a reference page, you can use the URL to figure out which version of the Framework it references. If you see the fully qualified name with nothing appended, then that is the latest release of the Framework. But if you see the name appended with VS.## then it is referencing a different version (#2). Here’s the breakdown.
.NET 3.5 Not appended. It is considered “the tip” so if you don’t qualify the URL, then you go to the latest version.
.NET 3.0 VS.85 (The first release of WPF)
.NET 2.0 VS.80
.NET 1.1 VS.71
So, in the example search above, you see that the first result is the .NET 3.5 WPF button. The second is the ASP button. And the third is the Silverlight button. Also, I did this search on MSDN, so they help you even more by adding the Related To: tags at the bottom of each result which lists the Framework version and general section of MSDN (Web Development, .NET Development, etc.).