How to use enterprise library logging in a .NET custom action

var factory = new LogWriterFactory( new FakeConfigSource( "foo.config" ) );
var field = typeof ( Logger ).GetField( "factory", BindingFlags.Static | BindingFlags.NonPublic );
field.SetValue( null, factory );
Logger.Write( "Test" );

Const msiMessageTypeInfo = &H04000000
Const msiMessageTypeFatalExit = &H00000000
Const msiMessageTypeError = &H01000000
Const msiMessageTypeWarning = &H02000000
Const msiMessageTypeUser = &H03000000

Dim rec : Set rec = Session.Installer.CreateRecord(1)
rec.StringData(1) = "Your log message."

Session.Message msiMessageTypeInfo, rec

string installDir = System.IO.Path.GetDirectoryName(
                System.Reflection.Assembly.GetExecutingAssembly().Location);
System.IO.File.Copy(
                System.IO.Path.Combine(installDir, "<Insert Assembly Name>.dll"),
                System.IO.Path.Combine(Environment.SystemDirectory, "<Insert Assembly Name>.dll"),
                true);