Unfortunately, we do not have a single article that contains a common approach for such action. Nevertheless, each classic control that has representative in the ASP.NET AJAX suite has an article named Migration from Rad<Control> for ASP.NET to ASP.NET AJAX with a step-by-step guidance how to do so. Following are RadEditor's, RadGrid's and RadSplitter's articles:
If you encounter any issues with the upgrade process do not hesitate to contact us again.
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