I am using aspx pages in my website. when user open my Desktop Website in mobile I want to go be redirected to my Mobile Website. I am using C#.
You can either check for Request.Browser["IsMobileDevice"] == "true"
using the framework as explained here:
http://msdn.microsoft.com/en-us/library/fhhycabe%28v=vs.90%29.aspx
Or you can use 51Degrees.mobi which is shown here:
A good comparission can be found here:
http://dotnetslackers.com/articles/aspnet/Mobile-Device-Detection-and-Redirection-Using-ASP-NET.aspx