Thank you for writing.
Printing only a selection of rows in RadGridView
is currently not supported. Moreover, when there is hierarchical data with multiple rows selected at different levels it is not clear how you would like them to be displayed when printed.
You could, however, use the existing API and specify which views be printed. Detailed information is available in the following documentation article: Printing Hierarchical Grid
As to your second question, I think that the best solution would be to hide the columns which you do not need and show them after the grid has been printed.
I hope this information helps. Should you have further questions please do not hesitate to write back.
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