Ofcourse you can do almost everything in Silverlight but not the wau u did for normal asp.net app.
With Silverlight u wont find the System.Web.UI whereas it is System.Windows namespace. So u gotta write Windows Form kinda code. No ASp.NET code u will be writting here.
Regardign controls: Al most all the control available in ASP.NET are available in equivalent version of Silverlight. So u can do everything u do with those ASP.NET controls.
Silverlight execution process is kind of javaScript so security is a concern. There are lot of things that u can do easily ASP.NET are not allowed to do it Silverligght. Like u can not use System.Diagnostics library directly. For these kind of security issues u can condiser Web Service or WCF.
Controls: : Lot many free open source controls are availavle codeplex site.
Soumen, India,
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