WPF C #: My text editor should be the default program for text files?

Question

I have developed a text editor with WPF C #. I want the user to have the possibility to make this text editor the standard software for text files. I researched that it needs to go through the Windows registry, but I do not know how.

I tried this, but it does not work:

private void standard programs for text files ()
    {
        RegistryKey vRegist;
        RegistryKey vKey;
        vRegist = Registry.ClassesRoot.OpenSubKey ("", true);
        vKey = vRegist.CreateSubKey (".txt");
        vKey.SetValue ("", "textfile");
        vKey = vRegist.CreateSubKey ("textfile");
        vKey.SetValue ("", "text file");
        vKey = vRegist.CreateSubKey (@ "textfile \ DefaultIcon");
        vKey.SetValue ("", System.IO.Path.GetDirectoryName (System.Reflection.Assembly.GetExecutingAssembly (). GetName (). CodeBase) + ".0");
        vKey = vRegist.CreateSubKey (@ "textfile \ shell \ open \ command");
        vKey.SetValue ("", System.IO.Path.GetDirectoryName (System.Reflection.Assembly.GetExecutingAssembly (). GetName (). CodeBase) + "% 1");
    }

But it does not work.

I want a code sample.