Best Way To Determine If .NET 3.5 Is Installed

Question

I need to programatically determine whether .NET 3.5 is installed. I thought it would be easy:

<% Response.Write(Environment.Version.ToString()); %>
         


        

Answer 1

@Kev, really like your solution. Thanks for the help.

Using the registry the code would look something like this:

RegistryKey key = Registry
        .LocalMachine
        .OpenSubKey("Software\\Microsoft\\NET Framework Setup\\NDP\\v3.5");
return (key != null);

I would be curious if either of these would work in a medium trust environment (although I am working in full trust so it doesn't matter to what I am currently working on).