The required actions is more related to a how-to export rendered ASP.NET AJAX control to different document format.
Each of these controls can export the content separately, but exporting the rendered HTML content is not related to any of the Telerik controls.
Such functionality would be complex and time-consuming matter, which should be built entirely by the developer of the application. Due to the reason that this is not related to the Telerik UI for ASP.NET AJAX suite I am unable to provide a proper approach to achieve that.
I can only suggest you searching for proper information through ASP.NET forums and communities for approach to export the rendered data to a desired format.
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