One of the major tenets of Test Studio is to keep coding to a minimum and only resort to it when you absolutely have to. You can simply Create a Web Test, navigate to your Silverlight app, and start performing actions and Verifications. Every element you act upon will be added to the Elements Explorer. Also see our article on How the Element Repository Works.
For those special cases that require a more complex solution, add a Coded Step. You can Reference an Existing Element and perform more advanced tasks if needed.
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