Hi Giancarlo,
The Grid as default support to the Drag / Drop operation by setting the AllowDrop property. The DragEnter and DragDrop are the two events, which gets fired during the starting and ending of the DragDrop operation. Refer this
sample for more details.
You can also refer to Broswer Sample \\Windows\Grid.Windows\Samples\Quick Start\OleDragDrop
Let us know if you need further assistance,
Regards,
Madhan.