FrameworkName supportedVer1 = new FrameworkName(".NET Framework, Version=4.0");
FrameworkName actualVersion = new FrameworkName(String.Format(
                                           ".NET Framework, Version={0}", 
                                           Environment.Version.ToString()));
                                           
Console.WriteLine("Supported Version: {0}", supportedVer1);
Console.WriteLine("Actual Version:    {0}", actualVersion);
if (supportedVer1 == actualVersion)    
   Console.WriteLine("The supported and actual Framework versions are the same.");
else
   Console.WriteLine("The supported and actual Framework versions are different.");

Console.WriteLine();