C# : Semak .NET

using Microsoft.Win32;
    using System.Globalization;

    private void button1_Click(object sender, EventArgs e)
            {
                RegistryKey installed_versions = Registry.LocalMachine.OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP");
                string[] version_names = installed_versions.GetSubKeyNames();
                double Framework = Convert.ToDouble(version_names[version_names.Length - 1].Remove(0, 1), CultureInfo.InvariantCulture);
                int ServicePack = Convert.ToInt32(installed_versions.OpenSubKey(version_names[version_names.Length - 1]).GetValue("SP", 0));
                MessageBox.Show(".NET " + Framework + "." + ServicePack);
            }