As of now, our Silverlight and WPF suites don't have such control. It is in our development plans, but we can't give you specific timeline for its development.
You can, however, use a different approach and visualize the PDF documents in ASP.NET webpage with content type set to "Application/pdf", relying on PDF viewer to be installed client-side:
Response.OutputStream.Write(data, 0, data.Length);
Don't hesitate to contact us if you have other questions.
the Telerik team
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