目前WPF 4对于混淆还是没有原生的支持。
http://blogs.windowsclient.net/rob_relyea/archive/2009/10/27/obfuscation-of-wpf-applications-status-update.aspx
有一位同学说他在SL上实验了一些混淆工具效果不错。
http://www.olsonsoft.com/blogs/stefanolson/post/Selecting-an-obfuscator-for-Silverlight.aspx
这些工具有：
.net reactor 4.1.0 (final release) - $179US DeepSea Obfuscator 2009 2.1.6.120 - $299US {smartassembly} 4.1.39 Professional Edition - $699US 还有一些他没实验的：
Spices.Net 5.6.6.0 - $699. At the time I started the evaluation they hadn't released a new version since Silverlight 3 was shipped and it is not clear what their Silverlight support was like Dotfuscator for .NET - ~$2000US. Too expensive. Crypto obfuscator - Enterprise edition $399US. Wasn't aware of it when I started this review. Eazfuscator.NET – Free. Needs to be added into the Visual Studio build process and looks too complicated. If there are others I've missed, please let me know. 里面有一些截图，效果还可以。
注意：Xaml/Baml是不可被混淆的。目前所有文章都这么说。
这些Blog中的评论也很有价值。
