There's demo at
http://www.9rays.net/asp.net_2/treeview/Demo_DragAndDrop.aspx
and doc at
http://www.9rays.net/asp.net_2/treeview/Doc_DragDrop.aspx
I believe you're calling something like
flytreeview_startDrag('dragname', \"value\", \"html\");
Tthe dragname parameter serves to detect whether the drop will be allowed (using DragDropAcceptNames property or acceptNames parameter of flytreeview_dragOver) and nothing more.
You should use the value parameter to pass value to server.
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