Is there any native compression (for javascript/css files) available in ASP.NET?
There is Gzip/Deflate compression support in IIS compatible with all modern browsers except IE6. For IIS 7 check this page: http://www.iis.net/ConfigReference/system.webServer/httpCompression
You could use Packer.
This utlity supports JavaScript compression and /or "minifying", and CSS "minifying".
It's available as a command line utility or also as an MSBuild task. This way you can integrate it into your build process / Visual Studio project.
In the appendix of Professional ASP.NET 3.5 Scott Hanselman talks about Packer for .NET. This will integrate with MSBuild and pack javascript files for production deployments etc.
Further to other answers and comments, you can use Yahoo!'s YUI Compressor and make it an MSBuild Task to integration it into your build and deployment process.
I have written something to do this for me, you can download it here: http://www.picnet.com.au/blogs/Guido/post/2009/12/10/Javascript-runtime-compilation-using-AspNet-and-Googles-Closure-Compiler.aspx
It uses Google's closure compiler which is pretty awesome.
Thanks
Guido
Try Chirpy. It mashes, minifies, and validates your javascript, stylesheet, and dotless files. You can use YUI Compressor or Google Closure Compiler.
Or, for more info, check out:
http://www.weirdlover.com/2010/05/22/visual-studio-add-in-for-dotless-js-and-css-files/