Page History
...
The OnDragEnter event fires when the user drags items into the client space of this control. The SourceCtrl contains the CtrlEntId of the tree from where the items are being dragged. The Items parameter is a comma delimited list of the items themselves. The Shift and Ctrl parameters indicate the current state of the SHIFT and CTRL keys respectively. They will be set to 1 if their respective keys are pressed.
See the Drag and Drop topic for more details.
