///

         /// 检测计算机已经安装的NetFramework版本

       ///

         internal void GetVersionFromRegistry()

         {

             using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine,

                 RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))

             {

                 foreach (string versionKeyName in ndpKey.GetSubKeyNames())

                 {

                     if (versionKeyName.StartsWith("v"))

                     {

                         RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);

                         string name = (string)versionKey.GetValue("Version", "");

                         string sp = versionKey.GetValue("SP", "").ToString();

                         string install = versionKey.GetValue("Install", "").ToString();

                         if (install == "") //no install info, ust be later

                             Console.WriteLine(versionKeyName + "  " + name);

                         else

                         {

                             if (sp != "" && install == "")

                             {

                                 Console.WriteLine(versionKeyName + "  " + name + "  SP" + sp);

                             }

                         }

                         if (name != "")

                         {

                             continue;

                         }

                         foreach (string subKeyName in versionKey.GetSubKeyNames())

                         {

                             RegistryKey subKey = versionKey.OpenSubKey(subKeyName);

                             name = (string)subKey.GetValue("Version", "");

                             if (name != "")

                                 sp = subKey.GetValue("SP", "").ToString();

                             install = subKey.GetValue("Install", "").ToString();

                             if (install == "") //no install info, ust be later

                                 Console.WriteLine(versionKeyName + "  " + name);

                             else

                             {

                                 if (sp != "" && install == "")

                                 {

                                     Console.WriteLine("  " + subKeyName + "  " + name + "  SP" + sp);

                                 }

                                 else if (install == "")

                                 {

                                     Console.WriteLine("  " + subKeyName + "  " + name);

                                 }

                             }

                         }

                     }

                 }

             }

         }