Thank you for writing.
You can properly get the clicked element by using the MouseEventArgs object. Please note that the current row is changed after the mouse is released so it is not suitable to take the value from it:
GridDataCellElement = TryCast(radGridView1.ElementTree.GetElementAtPoint(e.Location), GridDataCellElement)
The grid also has an built-in drag drop service that can be used: Drag and Drop
Let me know if I can assist you further.
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