Following are the answers of your questions in the same order:
- We tried reproducing the issue that you describe but to no avail.
It would be best if you could send us a sample project demonstrating the problem, so we can test
with your exact scenario.
However, it should be noted that fixes were made for the Drag and Drop functionality of RadTreeView since SP2, meaning that the issue at hand may be fixed already.
- You could implement copy behavior on drag and drop as custom logic (for example by handling the DragEnding event of RadTreeView). It will not be easy to implement such behavior in RadtReeView itself as there are many scenarios where such behavior is dangerous/unwanted.
- There are two choices if you want to interrupt a drag and drop operation
- setting the AllowDrop property of a RadTreeNode to false to forbid dropping on it.
- handling the DragEnding event of RadTreeView and implementing more complex logic that basing on the dragged node and the target node sets the Cancel property of the event arguments to true.
Hope that helps.
If you have any other suggestion regarding RadControls for WinForms we will be glad if you share them with us.
Thank you for you cooperation.
the Telerik team